91771308751 has 2 divisors, whose sum is σ = 91771308752. Its totient is φ = 91771308750.

The previous prime is 91771308697. The next prime is 91771308763. The reversal of 91771308751 is 15780317719.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91771308751 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 91771308695 and 91771308704.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91771368751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45885654375 + 45885654376.

It is an arithmetic number, because the mean of its divisors is an integer number (45885654376).

Almost surely, 2^91771308751 is an apocalyptic number.

91771308751 is a deficient number, since it is larger than the sum of its proper divisors (1).

91771308751 is an equidigital number, since it uses as much as digits as its factorization.

91771308751 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 370440, while the sum is 49.

The spelling of 91771308751 in words is "ninety-one billion, seven hundred seventy-one million, three hundred eight thousand, seven hundred fifty-one".