18790866 has 40 divisors (see below), whose sum is σ = 42394044. Its totient is φ = 6220800.

The previous prime is 18790853. The next prime is 18790873. The reversal of 18790866 is 66809781.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 18740241 + 50625 = 4329^2 + 225^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 30966 + ... + 31566.

Almost surely, 2^18790866 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18790866, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21197022).

18790866 is an abundant number, since it is smaller than the sum of its proper divisors (23603178).

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

18790866 is a wasteful number, since it uses less digits than its factorization.

18790866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 808 (or 799 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The square root of 18790866 is about 4334.8432497612. The cubic root of 18790866 is about 265.8575093779.

The spelling of 18790866 in words is "eighteen million, seven hundred ninety thousand, eight hundred sixty-six".