99720561768 has 32 divisors (see below), whose sum is σ = 252457123200. Its totient is φ = 32819424768.

The previous prime is 99720561739. The next prime is 99720561779. The reversal of 99720561768 is 86716502799.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26295721 + ... + 26299512.

It is an arithmetic number, because the mean of its divisors is an integer number (7889285100).

Almost surely, 2^99720561768 is an apocalyptic number.

It is an amenable number.

99720561768 is an abundant number, since it is smaller than the sum of its proper divisors (152736561432).

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

99720561768 is a wasteful number, since it uses less digits than its factorization.

99720561768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52595321 (or 52595317 counting only the distinct ones).

The product of its (nonzero) digits is 11430720, while the sum is 60.

The spelling of 99720561768 in words is "ninety-nine billion, seven hundred twenty million, five hundred sixty-one thousand, seven hundred sixty-eight".