91644613 has 2 divisors, whose sum is σ = 91644614. Its totient is φ = 91644612.

The previous prime is 91644607. The next prime is 91644629. The reversal of 91644613 is 31644619.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60808804 + 30835809 = 7798^2 + 5553^2 .

It is a cyclic number.

It is not a de Polignac number, because 91644613 - 2²¹ = 89547461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91644013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45822306 + 45822307.

It is an arithmetic number, because the mean of its divisors is an integer number (45822307).

Almost surely, 2^91644613 is an apocalyptic number.

It is an amenable number.

91644613 is a deficient number, since it is larger than the sum of its proper divisors (1).

91644613 is an equidigital number, since it uses as much as digits as its factorization.

91644613 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15552, while the sum is 34.

The square root of 91644613 is about 9573.1192931040. The cubic root of 91644613 is about 450.8537094175.

The spelling of 91644613 in words is "ninety-one million, six hundred forty-four thousand, six hundred thirteen".