91218191313 has 16 divisors (see below), whose sum is σ = 122045133056. Its totient is φ = 60601770000.

The previous prime is 91218191257. The next prime is 91218191347. The reversal of 91218191313 is 31319181219.

It is not a de Polignac number, because 91218191313 - 2⁶ = 91218191249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91218191413) 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, 8101938 + ... + 8113188.

It is an arithmetic number, because the mean of its divisors is an integer number (7627820816).

Almost surely, 2^91218191313 is an apocalyptic number.

It is an amenable number.

91218191313 is a deficient number, since it is larger than the sum of its proper divisors (30826941743).

91218191313 is a wasteful number, since it uses less digits than its factorization.

91218191313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20364.

The product of its digits is 11664, while the sum is 39.

The spelling of 91218191313 in words is "ninety-one billion, two hundred eighteen million, one hundred ninety-one thousand, three hundred thirteen".