91675561 has 2 divisors, whose sum is σ = 91675562. Its totient is φ = 91675560.

The previous prime is 91675553. The next prime is 91675609. The reversal of 91675561 is 16557619.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 91393600 + 281961 = 9560^2 + 531^2 .

It is a cyclic number.

It is not a de Polignac number, because 91675561 - 2³ = 91675553 is a prime.

It is not a weakly prime, because it can be changed into another prime (91675501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45837780 + 45837781.

It is an arithmetic number, because the mean of its divisors is an integer number (45837781).

Almost surely, 2^91675561 is an apocalyptic number.

It is an amenable number.

91675561 is a deficient number, since it is larger than the sum of its proper divisors (1).

91675561 is an equidigital number, since it uses as much as digits as its factorization.

91675561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 56700, while the sum is 40.

The square root of 91675561 is about 9574.7355577060. The cubic root of 91675561 is about 450.9044541723.

The spelling of 91675561 in words is "ninety-one million, six hundred seventy-five thousand, five hundred sixty-one".