64939718464 has 14 divisors (see below), whose sum is σ = 128864753954. Its totient is φ = 32469859200.

The previous prime is 64939718453. The next prime is 64939718491. The reversal of 64939718464 is 46481793946.

It can be written as a sum of positive squares in only one way, i.e., 40917198400 + 24022520064 = 202280^2 + 154992^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 507341487 + ... + 507341614.

Almost surely, 2^64939718464 is an apocalyptic number.

64939718464 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

64939718464 is a deficient number, since it is larger than the sum of its proper divisors (63925035490).

64939718464 is a wasteful number, since it uses less digits than its factorization.

64939718464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1014683113 (or 1014683103 counting only the distinct ones).

The product of its digits is 31352832, while the sum is 61.

The spelling of 64939718464 in words is "sixty-four billion, nine hundred thirty-nine million, seven hundred eighteen thousand, four hundred sixty-four".