656738768 has 30 divisors (see below), whose sum is σ = 1480177026. Its totient is φ = 281459136.

The previous prime is 656738759. The next prime is 656738783. The reversal of 656738768 is 867837656.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 439824784 + 216913984 = 20972^2 + 14728^2 .

It is a Harshad number since it is a multiple of its sum of digits (56).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 418055 + ... + 419622.

Almost surely, 2^656738768 is an apocalyptic number.

It is an amenable number.

656738768 is an abundant number, since it is smaller than the sum of its proper divisors (823438258).

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

656738768 is a wasteful number, since it uses less digits than its factorization.

656738768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 837699 (or 837686 counting only the distinct ones).

The product of its digits is 10160640, while the sum is 56.

The square root of 656738768 is about 25626.9149138167. The cubic root of 656738768 is about 869.2223499802. Note that the first 3 decimals are identical.

The spelling of 656738768 in words is "six hundred fifty-six million, seven hundred thirty-eight thousand, seven hundred sixty-eight".