90890181 has 20 divisors (see below), whose sum is σ = 141680352. Its totient is φ = 57957768.

The previous prime is 90890179. The next prime is 90890197. The reversal of 90890181 is 18109809.

It is not a de Polignac number, because 90890181 - 2¹ = 90890179 is a prime.

It is a super-2 number, since 2×90890181² = 16522050004425522, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90890101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 22531 + ... + 26256.

Almost surely, 2^90890181 is an apocalyptic number.

It is an amenable number.

90890181 is a deficient number, since it is larger than the sum of its proper divisors (50790171).

90890181 is a wasteful number, since it uses less digits than its factorization.

90890181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48822 (or 48813 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

The square root of 90890181 is about 9533.6341968842. The cubic root of 90890181 is about 449.6131341727.

The spelling of 90890181 in words is "ninety million, eight hundred ninety thousand, one hundred eighty-one".