91817249 has 2 divisors, whose sum is σ = 91817250. Its totient is φ = 91817248.

The previous prime is 91817233. The next prime is 91817251. The reversal of 91817249 is 94271819.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73839649 + 17977600 = 8593^2 + 4240^2 .

It is a cyclic number.

It is not a de Polignac number, because 91817249 - 2⁴ = 91817233 is a prime.

Together with 91817251, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (91817849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45908624 + 45908625.

It is an arithmetic number, because the mean of its divisors is an integer number (45908625).

Almost surely, 2^91817249 is an apocalyptic number.

It is an amenable number.

91817249 is a deficient number, since it is larger than the sum of its proper divisors (1).

91817249 is an equidigital number, since it uses as much as digits as its factorization.

91817249 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36288, while the sum is 41.

The square root of 91817249 is about 9582.1317565561. The cubic root of 91817249 is about 451.1366311532.

The spelling of 91817249 in words is "ninety-one million, eight hundred seventeen thousand, two hundred forty-nine".