91985851352917 has 2 divisors, whose sum is σ = 91985851352918. Its totient is φ = 91985851352916.

The previous prime is 91985851352881. The next prime is 91985851352921. The reversal of 91985851352917 is 71925315858919.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57981919951396 + 34003931401521 = 7614586^2 + 5831289^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91985851352917 is a prime.

It is a super-2 number, since 2×91985851352917² (a number of 29 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 91985851352917.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91985851332917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45992925676458 + 45992925676459.

It is an arithmetic number, because the mean of its divisors is an integer number (45992925676459).

Almost surely, 2^{91985851352917} is an apocalyptic number.

It is an amenable number.

91985851352917 is a deficient number, since it is larger than the sum of its proper divisors (1).

91985851352917 is an equidigital number, since it uses as much as digits as its factorization.

91985851352917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 244944000, while the sum is 73.

The spelling of 91985851352917 in words is "ninety-one trillion, nine hundred eighty-five billion, eight hundred fifty-one million, three hundred fifty-two thousand, nine hundred seventeen".