65561677616556 has 108 divisors (see below), whose sum is σ = 182599039771512. Its totient is φ = 19670469120000.

The previous prime is 65561677616507. The next prime is 65561677616569.

65561677616556 is a `hidden beast` number, since 6 + 5 + 5 + 6 + 1 + 6 + 7 + 7 + 61 + 6 + 556 = 666.

65561677616556 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×65561677616556² (a number of 28 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 4075285 + ... + 12154476.

Almost surely, 2^{65561677616556} is an apocalyptic number.

65561677616556 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

65561677616556 is an abundant number, since it is smaller than the sum of its proper divisors (117037362154956).

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

65561677616556 is a wasteful number, since it uses less digits than its factorization.

65561677616556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16229984 (or 16229878 counting only the distinct ones).

The product of its digits is 1428840000, while the sum is 72.

The spelling of 65561677616556 in words is "sixty-five trillion, five hundred sixty-one billion, six hundred seventy-seven million, six hundred sixteen thousand, five hundred fifty-six".