15979999680 has 224 divisors, whose sum is σ = 56756808000. Its totient is φ = 4232392704.

The previous prime is 15979999661. The next prime is 15979999687. The reversal of 15979999680 is 8699997951.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 15979999599 and 15979999608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15979999687) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1281154 + ... + 1293566.

Almost surely, 2^15979999680 is an apocalyptic number.

15979999680 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 15979999680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28378404000).

15979999680 is an abundant number, since it is smaller than the sum of its proper divisors (40776808320).

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

15979999680 is a wasteful number, since it uses less digits than its factorization.

15979999680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12588 (or 12572 counting only the distinct ones).

The product of its (nonzero) digits is 99202320, while the sum is 72.

The spelling of 15979999680 in words is "fifteen billion, nine hundred seventy-nine million, nine hundred ninety-nine thousand, six hundred eighty".