91375473857 has 2 divisors, whose sum is σ = 91375473858. Its totient is φ = 91375473856.

The previous prime is 91375473811. The next prime is 91375473877. The reversal of 91375473857 is 75837457319.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64267827121 + 27107646736 = 253511^2 + 164644^2 .

It is a cyclic number.

It is not a de Polignac number, because 91375473857 - 2¹⁴ = 91375457473 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 91375473796 and 91375473805.

It is not a weakly prime, because it can be changed into another prime (91375473877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45687736928 + 45687736929.

It is an arithmetic number, because the mean of its divisors is an integer number (45687736929).

Almost surely, 2^91375473857 is an apocalyptic number.

It is an amenable number.

91375473857 is a deficient number, since it is larger than the sum of its proper divisors (1).

91375473857 is an equidigital number, since it uses as much as digits as its factorization.

91375473857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22226400, while the sum is 59.

The spelling of 91375473857 in words is "ninety-one billion, three hundred seventy-five million, four hundred seventy-three thousand, eight hundred fifty-seven".