91604198920 has 384 divisors, whose sum is σ = 241757200800. Its totient is φ = 31157747712.

The previous prime is 91604198863. The next prime is 91604198927. The reversal of 91604198920 is 2989140619.

It is a happy number.

It can be written as a sum of positive squares in 48 ways, for example, as 10218379396 + 81385819524 = 101086^2 + 285282^2 .

It is not an unprimeable number, because it can be changed into a prime (91604198927) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 529503954 + ... + 529504126.

Almost surely, 2^91604198920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91604198920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120878600400).

91604198920 is an abundant number, since it is smaller than the sum of its proper divisors (150153001880).

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

91604198920 is a wasteful number, since it uses less digits than its factorization.

91604198920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 349 (or 332 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 49.

The spelling of 91604198920 in words is "ninety-one billion, six hundred four million, one hundred ninety-eight thousand, nine hundred twenty".