18990446 has 4 divisors (see below), whose sum is σ = 28485672. Its totient is φ = 9495222.

The previous prime is 18990427. The next prime is 18990451. The reversal of 18990446 is 64409981.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4747610 + ... + 4747613.

It is an arithmetic number, because the mean of its divisors is an integer number (7121418).

Almost surely, 2^18990446 is an apocalyptic number.

18990446 is a deficient number, since it is larger than the sum of its proper divisors (9495226).

18990446 is an equidigital number, since it uses as much as digits as its factorization.

18990446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9495225.

The product of its (nonzero) digits is 62208, while the sum is 41.

The square root of 18990446 is about 4357.8028867768. The cubic root of 18990446 is about 266.7954312166.

The spelling of 18990446 in words is "eighteen million, nine hundred ninety thousand, four hundred forty-six".