91866820 has 24 divisors (see below), whose sum is σ = 193737600. Its totient is φ = 36591072.

The previous prime is 91866799. The next prime is 91866851. The reversal of 91866820 is 2866819.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4830 + ... + 14389.

It is an arithmetic number, because the mean of its divisors is an integer number (8072400).

Almost surely, 2^91866820 is an apocalyptic number.

It is an amenable number.

91866820 is an abundant number, since it is smaller than the sum of its proper divisors (101870780).

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

91866820 is a wasteful number, since it uses less digits than its factorization.

91866820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19467 (or 19465 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 40.

The square root of 91866820 is about 9584.7180448879. The cubic root of 91866820 is about 451.2178042473.

The spelling of 91866820 in words is "ninety-one million, eight hundred sixty-six thousand, eight hundred twenty".