91909555579 has 2 divisors, whose sum is σ = 91909555580. Its totient is φ = 91909555578.

The previous prime is 91909555561. The next prime is 91909555601. The reversal of 91909555579 is 97555590919.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 91909555579 - 2¹⁵ = 91909522811 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 91909555579.

It is not a weakly prime, because it can be changed into another prime (91909555519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45954777789 + 45954777790.

It is an arithmetic number, because the mean of its divisors is an integer number (45954777790).

Almost surely, 2^91909555579 is an apocalyptic number.

91909555579 is a deficient number, since it is larger than the sum of its proper divisors (1).

91909555579 is an equidigital number, since it uses as much as digits as its factorization.

91909555579 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28704375, while the sum is 64.

The spelling of 91909555579 in words is "ninety-one billion, nine hundred nine million, five hundred fifty-five thousand, five hundred seventy-nine".