15999043912 has 8 divisors (see below), whose sum is σ = 29998207350. Its totient is φ = 7999521952.

The previous prime is 15999043891. The next prime is 15999043939. The reversal of 15999043912 is 21934099951.

It can be written as a sum of positive squares in only one way, i.e., 8185544676 + 7813499236 = 90474^2 + 88394^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 15999043912.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 999940237 + ... + 999940252.

Almost surely, 2^15999043912 is an apocalyptic number.

It is an amenable number.

15999043912 is a deficient number, since it is larger than the sum of its proper divisors (13999163438).

15999043912 is a wasteful number, since it uses less digits than its factorization.

15999043912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1999880495 (or 1999880491 counting only the distinct ones).

The product of its (nonzero) digits is 787320, while the sum is 52.

The spelling of 15999043912 in words is "fifteen billion, nine hundred ninety-nine million, forty-three thousand, nine hundred twelve".