91771945164 has 48 divisors (see below), whose sum is σ = 237968143840. Its totient is φ = 30585392640.

The previous prime is 91771945147. The next prime is 91771945193. The reversal of 91771945164 is 46154917719.

It is a happy number.

91771945164 is a `hidden beast` number, since 9 + 177 + 19 + 451 + 6 + 4 = 666.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 91771945164.

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, 585924 + ... + 725844.

Almost surely, 2^91771945164 is an apocalyptic number.

It is an amenable number.

91771945164 is an abundant number, since it is smaller than the sum of its proper divisors (146196198676).

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

91771945164 is a wasteful number, since it uses less digits than its factorization.

91771945164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146007 (or 145999 counting only the distinct ones).

The product of its digits is 1905120, while the sum is 54.

The spelling of 91771945164 in words is "ninety-one billion, seven hundred seventy-one million, nine hundred forty-five thousand, one hundred sixty-four".