18628866 has 32 divisors (see below), whose sum is σ = 41918400. Its totient is φ = 6208164.

The previous prime is 18628859. The next prime is 18628867. The reversal of 18628866 is 66882681.

18628866 is a `hidden beast` number, since 18 + 628 + 8 + 6 + 6 = 666.

It is not an unprimeable number, because it can be changed into a prime (18628867) by changing a digit.

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 in 15 ways as a sum of consecutive naturals, for example, 2245 + ... + 6503.

It is an arithmetic number, because the mean of its divisors is an integer number (1309950).

Almost surely, 2^18628866 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18628866, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20959200).

18628866 is an abundant number, since it is smaller than the sum of its proper divisors (23289534).

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

18628866 is an frugal number, since it uses more digits than its factorization.

18628866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4282 (or 4264 counting only the distinct ones).

The product of its digits is 221184, while the sum is 45.

The square root of 18628866 is about 4316.1170049015. The cubic root of 18628866 is about 265.0912987898.

The spelling of 18628866 in words is "eighteen million, six hundred twenty-eight thousand, eight hundred sixty-six".