18008551 has 12 divisors (see below), whose sum is σ = 20437312. Its totient is φ = 15840000.

The previous prime is 18008539. The next prime is 18008579. The reversal of 18008551 is 15580081.

It is not a de Polignac number, because 18008551 - 2⁵ = 18008519 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18008351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1351 + ... + 6151.

Almost surely, 2^18008551 is an apocalyptic number.

18008551 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

18008551 is a deficient number, since it is larger than the sum of its proper divisors (2428761).

18008551 is a wasteful number, since it uses less digits than its factorization.

18008551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4854 (or 4843 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 28.

The square root of 18008551 is about 4243.6483124783. The cubic root of 18008551 is about 262.1156327763.

The spelling of 18008551 in words is "eighteen million, eight thousand, five hundred fifty-one".