91285920 has 384 divisors, whose sum is σ = 372314880. Its totient is φ = 20643840.

The previous prime is 91285897. The next prime is 91285933. The reversal of 91285920 is 2958219.

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 63 ways as a sum of consecutive naturals, for example, 807784 + ... + 807896.

It is an arithmetic number, because the mean of its divisors is an integer number (969570).

Almost surely, 2^91285920 is an apocalyptic number.

91285920 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91285920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (186157440).

91285920 is an abundant number, since it is smaller than the sum of its proper divisors (281028960).

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

91285920 is a wasteful number, since it uses less digits than its factorization.

91285920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165 (or 151 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 91285920 is about 9554.3665410115. The cubic root of 91285920 is about 450.2647331170.

The spelling of 91285920 in words is "ninety-one million, two hundred eighty-five thousand, nine hundred twenty".