18563421 has 8 divisors (see below), whose sum is σ = 24844320. Its totient is φ = 12329072.

The previous prime is 18563417. The next prime is 18563429. The reversal of 18563421 is 12436581.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18563421 - 2² = 18563417 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18563429) 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, 10695 + ... + 12308.

It is an arithmetic number, because the mean of its divisors is an integer number (3105540).

Almost surely, 2^18563421 is an apocalyptic number.

It is an amenable number.

18563421 is a deficient number, since it is larger than the sum of its proper divisors (6280899).

18563421 is a wasteful number, since it uses less digits than its factorization.

18563421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23275.

The product of its digits is 5760, while the sum is 30.

The square root of 18563421 is about 4308.5288672585. The cubic root of 18563421 is about 264.7805041354.

The spelling of 18563421 in words is "eighteen million, five hundred sixty-three thousand, four hundred twenty-one".