79990861536 has 144 divisors (see below), whose sum is σ = 241171257600. Its totient is φ = 25078305024.

The previous prime is 79990861519. The next prime is 79990861541. The reversal of 79990861536 is 63516809997.

79990861536 is a `hidden beast` number, since 7 + 9 + 9 + 9 + 0 + 8 + 615 + 3 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 708025 + ... + 813191.

It is an arithmetic number, because the mean of its divisors is an integer number (1674800400).

Almost surely, 2^79990861536 is an apocalyptic number.

79990861536 is a gapful number since it is divisible by the number (76) 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 79990861536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120585628800).

79990861536 is an abundant number, since it is smaller than the sum of its proper divisors (161180396064).

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

79990861536 is a wasteful number, since it uses less digits than its factorization.

79990861536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105341 (or 105330 counting only the distinct ones).

The product of its (nonzero) digits is 22044960, while the sum is 63.

The spelling of 79990861536 in words is "seventy-nine billion, nine hundred ninety million, eight hundred sixty-one thousand, five hundred thirty-six".