90121418 has 16 divisors (see below), whose sum is σ = 140121960. Its totient is φ = 43436736.

The previous prime is 90121399. The next prime is 90121441. The reversal of 90121418 is 81412109.

It can be written as a sum of positive squares in 4 ways, for example, as 89548369 + 573049 = 9463^2 + 757^2 .

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2480 + ... + 13652.

Almost surely, 2^90121418 is an apocalyptic number.

90121418 is a deficient number, since it is larger than the sum of its proper divisors (50000542).

90121418 is a wasteful number, since it uses less digits than its factorization.

90121418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11321.

The product of its (nonzero) digits is 576, while the sum is 26.

The square root of 90121418 is about 9493.2301141392. The cubic root of 90121418 is about 448.3419112093.

The spelling of 90121418 in words is "ninety million, one hundred twenty-one thousand, four hundred eighteen".