657991052 has 24 divisors (see below), whose sum is σ = 1283390640. Its totient is φ = 293345280.

The previous prime is 657991039. The next prime is 657991093. The reversal of 657991052 is 250199756.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 657990994 and 657991012.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 253349 + ... + 255932.

It is an arithmetic number, because the mean of its divisors is an integer number (53474610).

Almost surely, 2^657991052 is an apocalyptic number.

It is an amenable number.

657991052 is a deficient number, since it is larger than the sum of its proper divisors (625399588).

657991052 is a wasteful number, since it uses less digits than its factorization.

657991052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 509321 (or 509319 counting only the distinct ones).

The product of its (nonzero) digits is 170100, while the sum is 44.

The square root of 657991052 is about 25651.3362614894. The cubic root of 657991052 is about 869.7744833191.

The spelling of 657991052 in words is "six hundred fifty-seven million, nine hundred ninety-one thousand, fifty-two".