91551751 has 2 divisors, whose sum is σ = 91551752. Its totient is φ = 91551750.

The previous prime is 91551737. The next prime is 91551781. The reversal of 91551751 is 15715519.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (15715519) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91551751 - 2⁷ = 91551623 is a prime.

It is a super-2 number, since 2×91551751² = 16763446222332002, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91551781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45775875 + 45775876.

It is an arithmetic number, because the mean of its divisors is an integer number (45775876).

Almost surely, 2^91551751 is an apocalyptic number.

91551751 is a deficient number, since it is larger than the sum of its proper divisors (1).

91551751 is an equidigital number, since it uses as much as digits as its factorization.

91551751 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7875, while the sum is 34.

The square root of 91551751 is about 9568.2679205800. The cubic root of 91551751 is about 450.7013770367.

The spelling of 91551751 in words is "ninety-one million, five hundred fifty-one thousand, seven hundred fifty-one".