15921061680 has 160 divisors (see below), whose sum is σ = 52317883584. Its totient is φ = 3991339008.

The previous prime is 15921061661. The next prime is 15921061693. The reversal of 15921061680 is 8616012951.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4947432 + ... + 4950648.

Almost surely, 2^15921061680 is an apocalyptic number.

15921061680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15921061680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26158941792).

15921061680 is an abundant number, since it is smaller than the sum of its proper divisors (36396821904).

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

15921061680 is a wasteful number, since it uses less digits than its factorization.

15921061680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4463 (or 4457 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 39.

The spelling of 15921061680 in words is "fifteen billion, nine hundred twenty-one million, sixty-one thousand, six hundred eighty".