91539081 has 12 divisors (see below), whose sum is σ = 133709940. Its totient is φ = 60339840.

The previous prime is 91539079. The next prime is 91539113. The reversal of 91539081 is 18093519.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 36542025 + 54997056 = 6045^2 + 7416^2 .

It is not a de Polignac number, because 91539081 - 2¹ = 91539079 is a prime.

It is a super-2 number, since 2×91539081² = 16758806700649122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (91539061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 56340 + ... + 57941.

It is an arithmetic number, because the mean of its divisors is an integer number (11142495).

Almost surely, 2^91539081 is an apocalyptic number.

It is an amenable number.

91539081 is a deficient number, since it is larger than the sum of its proper divisors (42170859).

91539081 is a wasteful number, since it uses less digits than its factorization.

91539081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114376 (or 114373 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

The square root of 91539081 is about 9567.6058133684. The cubic root of 91539081 is about 450.6805849717.

The spelling of 91539081 in words is "ninety-one million, five hundred thirty-nine thousand, eighty-one".