91212613 has 2 divisors, whose sum is σ = 91212614. Its totient is φ = 91212612.

The previous prime is 91212593. The next prime is 91212637. The reversal of 91212613 is 31621219.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 48205249 + 43007364 = 6943^2 + 6558^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91212613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91212683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45606306 + 45606307.

It is an arithmetic number, because the mean of its divisors is an integer number (45606307).

Almost surely, 2^91212613 is an apocalyptic number.

It is an amenable number.

91212613 is a deficient number, since it is larger than the sum of its proper divisors (1).

91212613 is an equidigital number, since it uses as much as digits as its factorization.

91212613 is an evil number, because the sum of its binary digits is even.

The product of its digits is 648, while the sum is 25.

The square root of 91212613 is about 9550.5294617628. The cubic root of 91212613 is about 450.1441727345.

The spelling of 91212613 in words is "ninety-one million, two hundred twelve thousand, six hundred thirteen".