687978961860 has 48 divisors (see below), whose sum is σ = 1941509154816. Its totient is φ = 182016479232.

The previous prime is 687978961841. The next prime is 687978961877. The reversal of 687978961860 is 68169879786.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45135357 + ... + 45150596.

It is an arithmetic number, because the mean of its divisors is an integer number (40448107392).

Almost surely, 2^687978961860 is an apocalyptic number.

687978961860 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

687978961860 is an abundant number, since it is smaller than the sum of its proper divisors (1253530192956).

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

687978961860 is a wasteful number, since it uses less digits than its factorization.

687978961860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90286092 (or 90286090 counting only the distinct ones).

The product of its (nonzero) digits is 438939648, while the sum is 75.

The spelling of 687978961860 in words is "six hundred eighty-seven billion, nine hundred seventy-eight million, nine hundred sixty-one thousand, eight hundred sixty".