18668238 has 16 divisors (see below), whose sum is σ = 37632000. Its totient is φ = 6173496.

The previous prime is 18668213. The next prime is 18668263. The reversal of 18668238 is 83286681.

It is an interprime number because it is at equal distance from previous prime (18668213) and next prime (18668263).

It is a super-2 number, since 2×18668238² = 697006220049288, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 18668238.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11488 + ... + 13011.

It is an arithmetic number, because the mean of its divisors is an integer number (2352000).

Almost surely, 2^18668238 is an apocalyptic number.

18668238 is an abundant number, since it is smaller than the sum of its proper divisors (18963762).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18668238 is a wasteful number, since it uses less digits than its factorization.

18668238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24631.

The product of its digits is 110592, while the sum is 42.

The square root of 18668238 is about 4320.6756416098. The cubic root of 18668238 is about 265.2779236809.

The spelling of 18668238 in words is "eighteen million, six hundred sixty-eight thousand, two hundred thirty-eight".