18623666 has 16 divisors (see below), whose sum is σ = 28545048. Its totient is φ = 9110400.

The previous prime is 18623639. The next prime is 18623699. The reversal of 18623666 is 66632681.

It can be written as a sum of positive squares in 4 ways, for example, as 13875625 + 4748041 = 3725^2 + 2179^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35486 + ... + 36006.

Almost surely, 2^18623666 is an apocalyptic number.

18623666 is a deficient number, since it is larger than the sum of its proper divisors (9921382).

18623666 is a wasteful number, since it uses less digits than its factorization.

18623666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 877.

The product of its digits is 62208, while the sum is 38.

The square root of 18623666 is about 4315.5145695502. The cubic root of 18623666 is about 265.0666309252.

The spelling of 18623666 in words is "eighteen million, six hundred twenty-three thousand, six hundred sixty-six".