90997720 has 32 divisors (see below), whose sum is σ = 223359120. Its totient is φ = 33089920.

The previous prime is 90997691. The next prime is 90997723. The reversal of 90997720 is 2779909.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90997723) 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 7 ways as a sum of consecutive naturals, for example, 102967 + ... + 103846.

Almost surely, 2^90997720 is an apocalyptic number.

It is an amenable number.

90997720 is an abundant number, since it is smaller than the sum of its proper divisors (132361400).

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

90997720 is a wasteful number, since it uses less digits than its factorization.

90997720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 206835 (or 206831 counting only the distinct ones).

The product of its (nonzero) digits is 71442, while the sum is 43.

The square root of 90997720 is about 9539.2725089495. The cubic root of 90997720 is about 449.7903879736.

The spelling of 90997720 in words is "ninety million, nine hundred ninety-seven thousand, seven hundred twenty".