91618481 has 2 divisors, whose sum is σ = 91618482. Its totient is φ = 91618480.

The previous prime is 91618459. The next prime is 91618487. The reversal of 91618481 is 18481619.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53290000 + 38328481 = 7300^2 + 6191^2 .

It is a cyclic number.

It is not a de Polignac number, because 91618481 - 2¹⁸ = 91356337 is a prime.

It is a super-2 number, since 2×91618481² = 16787892121494722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (91618487) 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, 45809240 + 45809241.

It is an arithmetic number, because the mean of its divisors is an integer number (45809241).

Almost surely, 2^91618481 is an apocalyptic number.

It is an amenable number.

91618481 is a deficient number, since it is larger than the sum of its proper divisors (1).

91618481 is an equidigital number, since it uses as much as digits as its factorization.

91618481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13824, while the sum is 38.

The square root of 91618481 is about 9571.7543324095. The cubic root of 91618481 is about 450.8108524553.

The spelling of 91618481 in words is "ninety-one million, six hundred eighteen thousand, four hundred eighty-one".