99090720 has 72 divisors (see below), whose sum is σ = 338151996. Its totient is φ = 26423808.

The previous prime is 99090689. The next prime is 99090763. The reversal of 99090720 is 2709099.

It can be written as a sum of positive squares in 2 ways, for example, as 91929744 + 7160976 = 9588^2 + 2676^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 32967 + ... + 35846.

Almost surely, 2^99090720 is an apocalyptic number.

99090720 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

99090720 is an abundant number, since it is smaller than the sum of its proper divisors (239061276).

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

99090720 is a wasteful number, since it uses less digits than its factorization.

99090720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68834 (or 68823 counting only the distinct ones).

The product of its (nonzero) digits is 10206, while the sum is 36.

The square root of 99090720 is about 9954.4321786830. The cubic root of 99090720 is about 462.7477630364.

The spelling of 99090720 in words is "ninety-nine million, ninety thousand, seven hundred twenty".