90912720 has 80 divisors (see below), whose sum is σ = 296677440. Its totient is φ = 22966272.

The previous prime is 90912691. The next prime is 90912727. The reversal of 90912720 is 2721909.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90912727) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5409 + ... + 14528.

It is an arithmetic number, because the mean of its divisors is an integer number (3708468).

Almost surely, 2^90912720 is an apocalyptic number.

It is an amenable number.

90912720 is an abundant number, since it is smaller than the sum of its proper divisors (205764720).

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

90912720 is a wasteful number, since it uses less digits than its factorization.

90912720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19972 (or 19966 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 30.

The square root of 90912720 is about 9534.8162016895. The cubic root of 90912720 is about 449.6502962100.

It can be divided in two parts, 9091 and 2720, that added together give a palindrome (11811).

The spelling of 90912720 in words is "ninety million, nine hundred twelve thousand, seven hundred twenty".