450731221 has 2 divisors, whose sum is σ = 450731222. Its totient is φ = 450731220.

The previous prime is 450731209. The next prime is 450731249. The reversal of 450731221 is 122137054.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 430355025 + 20376196 = 20745^2 + 4514^2 .

It is a cyclic number.

It is not a de Polignac number, because 450731221 - 2⁵ = 450731189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (450731921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 225365610 + 225365611.

It is an arithmetic number, because the mean of its divisors is an integer number (225365611).

Almost surely, 2^450731221 is an apocalyptic number.

It is an amenable number.

450731221 is a deficient number, since it is larger than the sum of its proper divisors (1).

450731221 is an equidigital number, since it uses as much as digits as its factorization.

450731221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 450731221 is about 21230.4314840749. The cubic root of 450731221 is about 766.7242755912.

Adding to 450731221 its reverse (122137054), we get a palindrome (572868275).

The spelling of 450731221 in words is "four hundred fifty million, seven hundred thirty-one thousand, two hundred twenty-one".