91924561 has 2 divisors, whose sum is σ = 91924562. Its totient is φ = 91924560.

The previous prime is 91924543. The next prime is 91924571. The reversal of 91924561 is 16542919.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 67963536 + 23961025 = 8244^2 + 4895^2 .

It is a cyclic number.

It is not a de Polignac number, because 91924561 - 2¹⁹ = 91400273 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 91924561.

It is not a weakly prime, because it can be changed into another prime (91924541) 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, 45962280 + 45962281.

It is an arithmetic number, because the mean of its divisors is an integer number (45962281).

Almost surely, 2^91924561 is an apocalyptic number.

It is an amenable number.

91924561 is a deficient number, since it is larger than the sum of its proper divisors (1).

91924561 is an equidigital number, since it uses as much as digits as its factorization.

91924561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19440, while the sum is 37.

The square root of 91924561 is about 9587.7297104163. The cubic root of 91924561 is about 451.3123190047.

The spelling of 91924561 in words is "ninety-one million, nine hundred twenty-four thousand, five hundred sixty-one".