18440185 has 16 divisors (see below), whose sum is σ = 22586256. Its totient is φ = 14450688.

The previous prime is 18440179. The next prime is 18440231. The reversal of 18440185 is 58104481.

It can be written as a sum of positive squares in 8 ways, for example, as 147456 + 18292729 = 384^2 + 4277^2 .

It is a 5-Lehmer number, since φ(18440185) divides (18440185-1)⁵.

It is a cyclic number.

It is not a de Polignac number, because 18440185 - 2¹⁷ = 18309113 is a prime.

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, 93507 + ... + 93703.

It is an arithmetic number, because the mean of its divisors is an integer number (1411641).

Almost surely, 2^18440185 is an apocalyptic number.

It is an amenable number.

18440185 is a deficient number, since it is larger than the sum of its proper divisors (4146071).

18440185 is a wasteful number, since it uses less digits than its factorization.

18440185 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 492.

The product of its (nonzero) digits is 5120, while the sum is 31.

The square root of 18440185 is about 4294.2036514353. The cubic root of 18440185 is about 264.1932746382.

The spelling of 18440185 in words is "eighteen million, four hundred forty thousand, one hundred eighty-five".