91939321824 has 48 divisors (see below), whose sum is σ = 275817967488. Its totient is φ = 26268377472.

The previous prime is 91939321823. The next prime is 91939321849. The reversal of 91939321824 is 42812393919.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91939321823) 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, 68406562 + ... + 68407905.

It is an arithmetic number, because the mean of its divisors is an integer number (5746207656).

Almost surely, 2^91939321824 is an apocalyptic number.

It is an amenable number.

91939321824 is an abundant number, since it is smaller than the sum of its proper divisors (183878645664).

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

91939321824 is a wasteful number, since it uses less digits than its factorization.

91939321824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136814487 (or 136814479 counting only the distinct ones).

The product of its digits is 839808, while the sum is 51.

The spelling of 91939321824 in words is "ninety-one billion, nine hundred thirty-nine million, three hundred twenty-one thousand, eight hundred twenty-four".