91921516656 has 40 divisors (see below), whose sum is σ = 237474800640. Its totient is φ = 30639101376.

The previous prime is 91921516567. The next prime is 91921516657. The reversal of 91921516656 is 65661512919.

It is a junction number, because it is equal to n+sod(n) for n = 91921516599 and 91921516608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91921516657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1927111 + ... + 1974233.

It is an arithmetic number, because the mean of its divisors is an integer number (5936870016).

Almost surely, 2^91921516656 is an apocalyptic number.

It is an amenable number.

91921516656 is an abundant number, since it is smaller than the sum of its proper divisors (145553283984).

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

91921516656 is a wasteful number, since it uses less digits than its factorization.

91921516656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87773 (or 87767 counting only the distinct ones).

The product of its digits is 874800, while the sum is 51.

The spelling of 91921516656 in words is "ninety-one billion, nine hundred twenty-one million, five hundred sixteen thousand, six hundred fifty-six".