91172039520 has 48 divisors (see below), whose sum is σ = 287191926000. Its totient is φ = 24312543744.

The previous prime is 91172039489. The next prime is 91172039573. The reversal of 91172039520 is 2593027119.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

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, 94970395 + ... + 94971354.

It is an arithmetic number, because the mean of its divisors is an integer number (5983165125).

Almost surely, 2^91172039520 is an apocalyptic number.

It is an amenable number.

91172039520 is an abundant number, since it is smaller than the sum of its proper divisors (196019886480).

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

91172039520 is a wasteful number, since it uses less digits than its factorization.

91172039520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189941767 (or 189941759 counting only the distinct ones).

The product of its (nonzero) digits is 34020, while the sum is 39.

The spelling of 91172039520 in words is "ninety-one billion, one hundred seventy-two million, thirty-nine thousand, five hundred twenty".