18990424 has 32 divisors (see below), whose sum is σ = 37882800. Its totient is φ = 8899200.

The previous prime is 18990379. The next prime is 18990427. The reversal of 18990424 is 42409981.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18990427) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14734 + ... + 15970.

Almost surely, 2^18990424 is an apocalyptic number.

It is an amenable number.

18990424 is a deficient number, since it is larger than the sum of its proper divisors (18892376).

18990424 is a wasteful number, since it uses less digits than its factorization.

18990424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1363 (or 1359 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 18990424 is about 4357.8003625683. The cubic root of 18990424 is about 266.7953281911.

The spelling of 18990424 in words is "eighteen million, nine hundred ninety thousand, four hundred twenty-four".