91864687020 has 24 divisors (see below), whose sum is σ = 257221123824. Its totient is φ = 24497249856.

The previous prime is 91864687003. The next prime is 91864687027. The reversal of 91864687020 is 2078646819.

It is not an unprimeable number, because it can be changed into a prime (91864687027) 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, 765538999 + ... + 765539118.

It is an arithmetic number, because the mean of its divisors is an integer number (10717546826).

Almost surely, 2^91864687020 is an apocalyptic number.

It is an amenable number.

91864687020 is an abundant number, since it is smaller than the sum of its proper divisors (165356436804).

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

91864687020 is a wasteful number, since it uses less digits than its factorization.

91864687020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1531078129 (or 1531078127 counting only the distinct ones).

The product of its (nonzero) digits is 1161216, while the sum is 51.

The spelling of 91864687020 in words is "ninety-one billion, eight hundred sixty-four million, six hundred eighty-seven thousand, twenty".