91215653 has 2 divisors, whose sum is σ = 91215654. Its totient is φ = 91215652.

The previous prime is 91215629. The next prime is 91215689. The reversal of 91215653 is 35651219.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 65642404 + 25573249 = 8102^2 + 5057^2 .

It is a cyclic number.

It is not a de Polignac number, because 91215653 - 2¹⁸ = 90953509 is a prime.

It is equal to p_5283455 and since 91215653 and 5283455 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91215613) 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, 45607826 + 45607827.

It is an arithmetic number, because the mean of its divisors is an integer number (45607827).

Almost surely, 2^91215653 is an apocalyptic number.

It is an amenable number.

91215653 is a deficient number, since it is larger than the sum of its proper divisors (1).

91215653 is an equidigital number, since it uses as much as digits as its factorization.

91215653 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8100, while the sum is 32.

The square root of 91215653 is about 9550.6886139168. The cubic root of 91215653 is about 450.1491735892.

The spelling of 91215653 in words is "ninety-one million, two hundred fifteen thousand, six hundred fifty-three".