18992421 has 24 divisors (see below), whose sum is σ = 32258240. Its totient is φ = 10818576.

The previous prime is 18992401. The next prime is 18992431. The reversal of 18992421 is 12429981.

It is not a de Polignac number, because 18992421 - 2⁶ = 18992357 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18992401) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 59755 + ... + 60071.

Almost surely, 2^18992421 is an apocalyptic number.

It is an amenable number.

18992421 is a deficient number, since it is larger than the sum of its proper divisors (13265819).

18992421 is an frugal number, since it uses more digits than its factorization.

18992421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 650 (or 327 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 18992421 is about 4358.0294859030. The cubic root of 18992421 is about 266.8046797744.

The spelling of 18992421 in words is "eighteen million, nine hundred ninety-two thousand, four hundred twenty-one".