99639072 has 120 divisors (see below), whose sum is σ = 315683676. Its totient is φ = 30647808.

The previous prime is 99639049. The next prime is 99639073. The reversal of 99639072 is 27093699.

99639072 is a `hidden beast` number, since 9 + 9 + 639 + 0 + 7 + 2 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 86936976 + 12702096 = 9324^2 + 3564^2 .

It is not an unprimeable number, because it can be changed into a prime (99639073) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 32218 + ... + 35174.

Almost surely, 2^99639072 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 99639072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (157841838).

99639072 is an abundant number, since it is smaller than the sum of its proper divisors (216044604).

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

99639072 is a wasteful number, since it uses less digits than its factorization.

99639072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2992 (or 2975 counting only the distinct ones).

The product of its (nonzero) digits is 183708, while the sum is 45.

The square root of 99639072 is about 9981.9372869198. The cubic root of 99639072 is about 463.5997837136.

The spelling of 99639072 in words is "ninety-nine million, six hundred thirty-nine thousand, seventy-two".