91436981 has 2 divisors, whose sum is σ = 91436982. Its totient is φ = 91436980.

The previous prime is 91436927. The next prime is 91437013. The reversal of 91436981 is 18963419.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 91374481 + 62500 = 9559^2 + 250^2 .

It is a cyclic number.

It is not a de Polignac number, because 91436981 - 2¹⁴ = 91420597 is a prime.

It is a super-2 number, since 2×91436981² = 16721442988788722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91436921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45718490 + 45718491.

It is an arithmetic number, because the mean of its divisors is an integer number (45718491).

Almost surely, 2^91436981 is an apocalyptic number.

It is an amenable number.

91436981 is a deficient number, since it is larger than the sum of its proper divisors (1).

91436981 is an equidigital number, since it uses as much as digits as its factorization.

91436981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 41.

The square root of 91436981 is about 9562.2686115796. The cubic root of 91436981 is about 450.5129640111.

The spelling of 91436981 in words is "ninety-one million, four hundred thirty-six thousand, nine hundred eighty-one".