64660786720 has 48 divisors (see below), whose sum is σ = 152807157720. Its totient is φ = 25856518144.

The previous prime is 64660786691. The next prime is 64660786733. The reversal of 64660786720 is 2768706646.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 64518032016 + 142754704 = 254004^2 + 11948^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 486876 + ... + 605284.

Almost surely, 2^64660786720 is an apocalyptic number.

It is an amenable number.

64660786720 is an abundant number, since it is smaller than the sum of its proper divisors (88146371000).

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

64660786720 is a wasteful number, since it uses less digits than its factorization.

64660786720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121837 (or 121829 counting only the distinct ones).

The product of its (nonzero) digits is 4064256, while the sum is 52.

The spelling of 64660786720 in words is "sixty-four billion, six hundred sixty million, seven hundred eighty-six thousand, seven hundred twenty".