77127528681 has 12 divisors (see below), whose sum is σ = 127321634752. Its totient is φ = 44072873496.

The previous prime is 77127528677. The next prime is 77127528713. The reversal of 77127528681 is 18682572177.

It is not a de Polignac number, because 77127528681 - 2² = 77127528677 is a prime.

It is a super-2 number, since 2×77127528681² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77127528601) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 612123181 + ... + 612123306.

Almost surely, 2^77127528681 is an apocalyptic number.

It is an amenable number.

77127528681 is a deficient number, since it is larger than the sum of its proper divisors (50194106071).

77127528681 is a wasteful number, since it uses less digits than its factorization.

77127528681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1224246500 (or 1224246497 counting only the distinct ones).

The product of its digits is 2634240, while the sum is 54.

The spelling of 77127528681 in words is "seventy-seven billion, one hundred twenty-seven million, five hundred twenty-eight thousand, six hundred eighty-one".