# Romatic Numbers with Python

python day 22

Today we will introduce two kinds of interesting number: **Narcissistic** Number, **Perfect** Number, and **Prime** Number.

**Narcissistic Number**

numbers that can be represented as the sum of the cube of each digits.

def nar():

for x in range (1,1001):

s=x%10

t=x//10%10

h=x//100

if x==s**3+t**3+h**3:

print("%d is a narcissistic number" %x)nar()

1 is a narcissistic number

153 is a narcissistic number

370 is a narcissistic number

371 is a narcissistic number

407 is a narcissistic number

1000 is a narcissistic number

**Perfect Number**

the number is equal to its sum of proper divisors.

from math import sqrt

def perfect(m):

for i in range (1,m):

s=0

for factor in range (1, int(sqrt(i))+1):

if i % factor==0:

s +=factor

if factor >1 and i//factor != factor:

s+= i//factor

if s==i:

print(i,"is a perfect number" )

print("So you are perfect2!")perfect(10000)1 is a perfect number

6 is a perfect number

28 is a perfect number

496 is a perfect number

8128 is a perfect number

So you are perfect2!

Once, i thought l is 8128, but now i know, that’s bc he is in C. everything about him has an “i” attached to it.

I just didnt notice/face it back then.

I think i like ppl in R! Keep Real!

就像 Yibo! 喜欢，不喜欢都说出来！

有什么大不了的！

**Prime**Number

The only divisor of the number is 1 and itself

from math import sqrt

def prime(m):

for i in range (2,m):

isprime=True

for factor in range (2, int(sqrt(i))+1):

if i % factor ==0:

isprime=False

break

if isprime:

print(i)prime(100)2

3

5

7

11

13

17

19

23

29

31

37

41

43

47

53

59

61

67

71

73

79

83

89

97

Story time:

Narcissistic flower is daffodil, a handsome boy fell in love with the beauty of himself when he saw himself in the lake.

he became a daffodil so he can look at himself all day long!

Happy studying!

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