657430121 has 16 divisors (see below), whose sum is σ = 684702480. Its totient is φ = 630789120.

The previous prime is 657430117. The next prime is 657430127. The reversal of 657430121 is 121034756.

It can be written as a sum of positive squares in 8 ways, for example, as 188101225 + 469328896 = 13715^2 + 21664^2 .

It is a cyclic number.

It is not a de Polignac number, because 657430121 - 2² = 657430117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (657430127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 701165 + ... + 702101.

It is an arithmetic number, because the mean of its divisors is an integer number (42793905).

Almost surely, 2^657430121 is an apocalyptic number.

It is an amenable number.

657430121 is a deficient number, since it is larger than the sum of its proper divisors (27272359).

657430121 is a wasteful number, since it uses less digits than its factorization.

657430121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1244.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 657430121 is about 25640.4001723842. The cubic root of 657430121 is about 869.5272549444.

Adding to 657430121 its reverse (121034756), we get a palindrome (778464877).

The spelling of 657430121 in words is "six hundred fifty-seven million, four hundred thirty thousand, one hundred twenty-one".