90997281 has 12 divisors (see below), whose sum is σ = 132312960. Its totient is φ = 60262200.

The previous prime is 90997267. The next prime is 90997301. The reversal of 90997281 is 18279909.

It is not a de Polignac number, because 90997281 - 2⁹ = 90996769 is a prime.

It is a super-2 number, since 2×90997281² = 16561010298785922, which contains 22 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (90997241) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 32121 + ... + 34838.

It is an arithmetic number, because the mean of its divisors is an integer number (11026080).

Almost surely, 2^90997281 is an apocalyptic number.

It is an amenable number.

90997281 is a deficient number, since it is larger than the sum of its proper divisors (41315679).

90997281 is a wasteful number, since it uses less digits than its factorization.

90997281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67116 (or 67113 counting only the distinct ones).

The product of its (nonzero) digits is 81648, while the sum is 45.

The square root of 90997281 is about 9539.2494987813. The cubic root of 90997281 is about 449.7896646651.

The spelling of 90997281 in words is "ninety million, nine hundred ninety-seven thousand, two hundred eighty-one".