15987998816 has 48 divisors (see below), whose sum is σ = 33047889840. Its totient is φ = 7603115520.

The previous prime is 15987998813. The next prime is 15987998839. The reversal of 15987998816 is 61889978951.

It is a super-2 number, since 2×15987998816² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 15987998816.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15987998813) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 66395 + ... + 190746.

It is an arithmetic number, because the mean of its divisors is an integer number (688497705).

Almost surely, 2^15987998816 is an apocalyptic number.

15987998816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

15987998816 is an abundant number, since it is smaller than the sum of its proper divisors (17059891024).

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

15987998816 is a wasteful number, since it uses less digits than its factorization.

15987998816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257247 (or 257239 counting only the distinct ones).

The product of its digits is 78382080, while the sum is 71.

The spelling of 15987998816 in words is "fifteen billion, nine hundred eighty-seven million, nine hundred ninety-eight thousand, eight hundred sixteen".