18681868 has 24 divisors (see below), whose sum is σ = 33454512. Its totient is φ = 9126144.

The previous prime is 18681863. The next prime is 18681899. The reversal of 18681868 is 86818681.

It is not an unprimeable number, because it can be changed into a prime (18681863) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39771 + ... + 40237.

It is an arithmetic number, because the mean of its divisors is an integer number (1393938).

Almost surely, 2^18681868 is an apocalyptic number.

It is an amenable number.

18681868 is a deficient number, since it is larger than the sum of its proper divisors (14772644).

18681868 is a wasteful number, since it uses less digits than its factorization.

18681868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 681 (or 679 counting only the distinct ones).

The product of its digits is 147456, while the sum is 46.

The square root of 18681868 is about 4322.2526534204. The cubic root of 18681868 is about 265.3424692920.

The spelling of 18681868 in words is "eighteen million, six hundred eighty-one thousand, eight hundred sixty-eight".