15999680 has 28 divisors (see below), whose sum is σ = 38100000. Its totient is φ = 6399744.

The previous prime is 15999649. The next prime is 15999701. The reversal of 15999680 is 8699951.

It is a hoax number, since the sum of its digits (47) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24680 + ... + 25319.

Almost surely, 2^15999680 is an apocalyptic number.

15999680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15999680 is an abundant number, since it is smaller than the sum of its proper divisors (22100320).

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

15999680 is an equidigital number, since it uses as much as digits as its factorization.

15999680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50016 (or 50006 counting only the distinct ones).

The product of its (nonzero) digits is 174960, while the sum is 47.

The square root of 15999680 is about 3999.9599998000. The cubic root of 15999680 is about 251.9825300730.

The spelling of 15999680 in words is "fifteen million, nine hundred ninety-nine thousand, six hundred eighty".