91445569 has 2 divisors, whose sum is σ = 91445570. Its totient is φ = 91445568.

The previous prime is 91445561. The next prime is 91445573. The reversal of 91445569 is 96554419.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 59861169 + 31584400 = 7737^2 + 5620^2 .

It is a cyclic number.

It is not a de Polignac number, because 91445569 - 2³ = 91445561 is a prime.

It is a super-2 number, since 2×91445569² = 16724584179467522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (91445561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45722784 + 45722785.

It is an arithmetic number, because the mean of its divisors is an integer number (45722785).

Almost surely, 2^91445569 is an apocalyptic number.

It is an amenable number.

91445569 is a deficient number, since it is larger than the sum of its proper divisors (1).

91445569 is an equidigital number, since it uses as much as digits as its factorization.

91445569 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 194400, while the sum is 43.

The square root of 91445569 is about 9562.7176576536. The cubic root of 91445569 is about 450.5270680208.

The spelling of 91445569 in words is "ninety-one million, four hundred forty-five thousand, five hundred sixty-nine".