91030681 has 27 divisors (see below), whose sum is σ = 112053279. Its totient is φ = 73732848.

The previous prime is 91030669. The next prime is 91030703. The reversal of 91030681 is 18603019.

It is a happy number.

The square root of 91030681 is 9541.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 47734281 + 43296400 = 6909^2 + 6580^2 .

It is not a de Polignac number, because 91030681 - 2⁵ = 91030649 is a prime.

It is a super-2 number, since 2×91030681² = 16573169766647522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91030651) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1936800 + ... + 1936846.

Almost surely, 2^91030681 is an apocalyptic number.

91030681 is the 9541-st square number.

91030681 is the 4771-st centered octagonal number.

It is an amenable number.

91030681 is a deficient number, since it is larger than the sum of its proper divisors (21022598).

91030681 is an equidigital number, since it uses as much as digits as its factorization.

91030681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166 (or 83 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 28.

The cubic root of 91030681 is about 449.8446887895.

Multiplying 91030681 by its product of nonzero digits (1296), we get a square (117975762576 = 343476²).

The spelling of 91030681 in words is "ninety-one million, thirty thousand, six hundred eighty-one".