687968064 has 84 divisors (see below), whose sum is σ = 2253654624. Its totient is φ = 196561152.

The previous prime is 687968059. The next prime is 687968101. The reversal of 687968064 is 460869786.

It is a tau number, because it is divible by the number of its divisors (84).

It is a self number, because there is not a number n which added to its sum of digits gives 687968064.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 81282 + ... + 89345.

Almost surely, 2^687968064 is an apocalyptic number.

687968064 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

687968064 is an abundant number, since it is smaller than the sum of its proper divisors (1565686560).

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

687968064 is a wasteful number, since it uses less digits than its factorization.

687968064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170652 (or 170639 counting only the distinct ones).

The product of its (nonzero) digits is 3483648, while the sum is 54.

The square root of 687968064 is about 26229.1453158505. The cubic root of 687968064 is about 882.7873328136.

The spelling of 687968064 in words is "six hundred eighty-seven million, nine hundred sixty-eight thousand, sixty-four".