65687771928 has 64 divisors (see below), whose sum is σ = 173950830720. Its totient is φ = 20599462400.

The previous prime is 65687771923. The next prime is 65687771951. The reversal of 65687771928 is 82917778656.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65687771921) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1000843 + ... + 1064453.

It is an arithmetic number, because the mean of its divisors is an integer number (2717981730).

Almost surely, 2^65687771928 is an apocalyptic number.

65687771928 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

65687771928 is an abundant number, since it is smaller than the sum of its proper divisors (108263058792).

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

65687771928 is a wasteful number, since it uses less digits than its factorization.

65687771928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66168 (or 66164 counting only the distinct ones).

The product of its digits is 71124480, while the sum is 66.

The spelling of 65687771928 in words is "sixty-five billion, six hundred eighty-seven million, seven hundred seventy-one thousand, nine hundred twenty-eight".