91821120 has 112 divisors (see below), whose sum is σ = 294729408. Its totient is φ = 24217600.

The previous prime is 91821113. The next prime is 91821139. The reversal of 91821120 is 2112819.

It is a super-2 number, since 2×91821120² = 16862236156108800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 96487 + ... + 97433.

Almost surely, 2^91821120 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91821120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147364704).

91821120 is an abundant number, since it is smaller than the sum of its proper divisors (202908288).

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

91821120 is a wasteful number, since it uses less digits than its factorization.

91821120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1068 (or 1058 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 24.

The square root of 91821120 is about 9582.3337449705. Note that the first 3 decimals coincide. The cubic root of 91821120 is about 451.1429710126.

Adding to 91821120 its reverse (2112819), we get a palindrome (93933939).

The spelling of 91821120 in words is "ninety-one million, eight hundred twenty-one thousand, one hundred twenty".