91865771 has 2 divisors, whose sum is σ = 91865772. Its totient is φ = 91865770.

The previous prime is 91865743. The next prime is 91865819. The reversal of 91865771 is 17756819.

It is a weak prime.

It is an emirp because it is prime and its reverse (17756819) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91865771 - 2¹⁸ = 91603627 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (91865701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45932885 + 45932886.

It is an arithmetic number, because the mean of its divisors is an integer number (45932886).

Almost surely, 2^91865771 is an apocalyptic number.

91865771 is a deficient number, since it is larger than the sum of its proper divisors (1).

91865771 is an equidigital number, since it uses as much as digits as its factorization.

91865771 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 105840, while the sum is 44.

The square root of 91865771 is about 9584.6633222039. The cubic root of 91865771 is about 451.2160868000.

The spelling of 91865771 in words is "ninety-one million, eight hundred sixty-five thousand, seven hundred seventy-one".