91864249 has 2 divisors, whose sum is σ = 91864250. Its totient is φ = 91864248.

The previous prime is 91864237. The next prime is 91864291. The reversal of 91864249 is 94246819.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84052224 + 7812025 = 9168^2 + 2795^2 .

It is an emirp because it is prime and its reverse (94246819) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91864249 - 2²³ = 83475641 is a prime.

It is not a weakly prime, because it can be changed into another prime (91864049) 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, 45932124 + 45932125.

It is an arithmetic number, because the mean of its divisors is an integer number (45932125).

Almost surely, 2^91864249 is an apocalyptic number.

It is an amenable number.

91864249 is a deficient number, since it is larger than the sum of its proper divisors (1).

91864249 is an equidigital number, since it uses as much as digits as its factorization.

91864249 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 124416, while the sum is 43.

The square root of 91864249 is about 9584.5839241983. The cubic root of 91864249 is about 451.2135949227.

The spelling of 91864249 in words is "ninety-one million, eight hundred sixty-four thousand, two hundred forty-nine".