90398881 has 4 divisors (see below), whose sum is σ = 92842132. Its totient is φ = 87955632.

The previous prime is 90398851. The next prime is 90398899. The reversal of 90398881 is 18889309.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 38688400 + 51710481 = 6220^2 + 7191^2 .

It is a cyclic number.

It is not a de Polignac number, because 90398881 - 2⁵ = 90398849 is a prime.

It is a super-2 number, since 2×90398881² = 16343915372104322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90398801) 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 in 3 ways as a sum of consecutive naturals, for example, 1221570 + ... + 1221643.

It is an arithmetic number, because the mean of its divisors is an integer number (23210533).

Almost surely, 2^90398881 is an apocalyptic number.

It is an amenable number.

90398881 is a deficient number, since it is larger than the sum of its proper divisors (2443251).

90398881 is a wasteful number, since it uses less digits than its factorization.

90398881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2443250.

The product of its (nonzero) digits is 124416, while the sum is 46.

The square root of 90398881 is about 9507.8326131669. The cubic root of 90398881 is about 448.8015535002.

The spelling of 90398881 in words is "ninety million, three hundred ninety-eight thousand, eight hundred eighty-one".