90918215 has 16 divisors (see below), whose sum is σ = 111191808. Its totient is φ = 71352576.

The previous prime is 90918187. The next prime is 90918239. The reversal of 90918215 is 51281909.

It is a cyclic number.

It is not a de Polignac number, because 90918215 - 2¹² = 90914119 is a prime.

It is a super-2 number, since 2×90918215² = 16532243637572450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 80837 + ... + 81953.

It is an arithmetic number, because the mean of its divisors is an integer number (6949488).

Almost surely, 2^90918215 is an apocalyptic number.

90918215 is a deficient number, since it is larger than the sum of its proper divisors (20273593).

90918215 is a wasteful number, since it uses less digits than its factorization.

90918215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1418.

The product of its (nonzero) digits is 6480, while the sum is 35.

The square root of 90918215 is about 9535.1043518149. The cubic root of 90918215 is about 449.6593553699.

The spelling of 90918215 in words is "ninety million, nine hundred eighteen thousand, two hundred fifteen".