91820920 has 32 divisors (see below), whose sum is σ = 217472400. Its totient is φ = 34795008.

The previous prime is 91820903. The next prime is 91820923. The reversal of 91820920 is 2902819.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91820923) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59649 + ... + 61168.

Almost surely, 2^91820920 is an apocalyptic number.

It is an amenable number.

91820920 is an abundant number, since it is smaller than the sum of its proper divisors (125651480).

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

91820920 is a wasteful number, since it uses less digits than its factorization.

91820920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120847 (or 120843 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 91820920 is about 9582.3233090937. The cubic root of 91820920 is about 451.1426434603.

The spelling of 91820920 in words is "ninety-one million, eight hundred twenty thousand, nine hundred twenty".