657439968 has 24 divisors (see below), whose sum is σ = 1725780168. Its totient is φ = 219146624.

The previous prime is 657439967. The next prime is 657439969. The reversal of 657439968 is 869934756.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (657439967) and next prime (657439969).

It is a tau number, because it is divible by the number of its divisors (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (657439967) 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 3 ways as a sum of consecutive naturals, for example, 3424071 + ... + 3424262.

It is an arithmetic number, because the mean of its divisors is an integer number (71907507).

Almost surely, 2^657439968 is an apocalyptic number.

It is an amenable number.

657439968 is an abundant number, since it is smaller than the sum of its proper divisors (1068340200).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

657439968 is a wasteful number, since it uses less digits than its factorization.

657439968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6848346 (or 6848338 counting only the distinct ones).

The product of its digits is 9797760, while the sum is 57.

The square root of 657439968 is about 25640.5921928492. The cubic root of 657439968 is about 869.5315961876.

The spelling of 657439968 in words is "six hundred fifty-seven million, four hundred thirty-nine thousand, nine hundred sixty-eight".