91120212021 has 16 divisors (see below), whose sum is σ = 124861365504. Its totient is φ = 59065147584.

The previous prime is 91120211993. The next prime is 91120212061. The reversal of 91120212021 is 12021202119.

It is not a de Polignac number, because 91120212021 - 2¹⁵ = 91120179253 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91120212061) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 110970 + ... + 441083.

It is an arithmetic number, because the mean of its divisors is an integer number (7803835344).

Almost surely, 2^91120212021 is an apocalyptic number.

It is an amenable number.

91120212021 is a deficient number, since it is larger than the sum of its proper divisors (33741153483).

91120212021 is a wasteful number, since it uses less digits than its factorization.

91120212021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 553580.

The product of its (nonzero) digits is 144, while the sum is 21.

The spelling of 91120212021 in words is "ninety-one billion, one hundred twenty million, two hundred twelve thousand, twenty-one".