91115537 has 2 divisors, whose sum is σ = 91115538. Its totient is φ = 91115536.

The previous prime is 91115527. The next prime is 91115569. The reversal of 91115537 is 73551119.

It is a happy number.

It is an a-pointer prime, because the next prime (91115569) can be obtained adding 91115537 to its sum of digits (32).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73942801 + 17172736 = 8599^2 + 4144^2 .

It is an emirp because it is prime and its reverse (73551119) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91115537 - 2¹⁴ = 91099153 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (91115527) 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, 45557768 + 45557769.

It is an arithmetic number, because the mean of its divisors is an integer number (45557769).

Almost surely, 2^91115537 is an apocalyptic number.

It is an amenable number.

91115537 is a deficient number, since it is larger than the sum of its proper divisors (1).

91115537 is an equidigital number, since it uses as much as digits as its factorization.

91115537 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4725, while the sum is 32.

The square root of 91115537 is about 9545.4458774852. The cubic root of 91115537 is about 449.9844225060.

The spelling of 91115537 in words is "ninety-one million, one hundred fifteen thousand, five hundred thirty-seven".