18220168 has 8 divisors (see below), whose sum is σ = 34162830. Its totient is φ = 9110080.

The previous prime is 18220159. The next prime is 18220171. The reversal of 18220168 is 86102281.

It can be written as a sum of positive squares in only one way, i.e., 14915044 + 3305124 = 3862^2 + 1818^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1138753 + ... + 1138768.

Almost surely, 2^18220168 is an apocalyptic number.

It is an amenable number.

18220168 is a deficient number, since it is larger than the sum of its proper divisors (15942662).

18220168 is a wasteful number, since it uses less digits than its factorization.

18220168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2277527 (or 2277523 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 18220168 is about 4268.5088731312. The cubic root of 18220168 is about 263.1383370111.

The spelling of 18220168 in words is "eighteen million, two hundred twenty thousand, one hundred sixty-eight".