68657689928 has 8 divisors (see below), whose sum is σ = 128733168630. Its totient is φ = 34328844960.

The previous prime is 68657689853. The next prime is 68657689987. The reversal of 68657689928 is 82998675686.

It can be written as a sum of positive squares in only one way, i.e., 60871745284 + 7785944644 = 246722^2 + 88238^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4291105613 + ... + 4291105628.

Almost surely, 2^68657689928 is an apocalyptic number.

It is an amenable number.

68657689928 is a deficient number, since it is larger than the sum of its proper divisors (60075478702).

68657689928 is a wasteful number, since it uses less digits than its factorization.

68657689928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8582211247 (or 8582211243 counting only the distinct ones).

The product of its digits is 627056640, while the sum is 74.

The spelling of 68657689928 in words is "sixty-eight billion, six hundred fifty-seven million, six hundred eighty-nine thousand, nine hundred twenty-eight".