91911751 has 2 divisors, whose sum is σ = 91911752. Its totient is φ = 91911750.

The previous prime is 91911733. The next prime is 91911761. The reversal of 91911751 is 15711919.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 91911751 - 2⁵ = 91911719 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91911731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45955875 + 45955876.

It is an arithmetic number, because the mean of its divisors is an integer number (45955876).

Almost surely, 2^91911751 is an apocalyptic number.

91911751 is the 5125-th centered heptagonal number.

91911751 is a deficient number, since it is larger than the sum of its proper divisors (1).

91911751 is an equidigital number, since it uses as much as digits as its factorization.

91911751 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2835, while the sum is 34.

The square root of 91911751 is about 9587.0616457807. The cubic root of 91911751 is about 451.2913540623.

The spelling of 91911751 in words is "ninety-one million, nine hundred eleven thousand, seven hundred fifty-one".