18942621 has 4 divisors (see below), whose sum is σ = 25256832. Its totient is φ = 12628412.

The previous prime is 18942619. The next prime is 18942647. The reversal of 18942621 is 12624981.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18942621 - 2¹ = 18942619 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18942691) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3157101 + ... + 3157106.

It is an arithmetic number, because the mean of its divisors is an integer number (6314208).

Almost surely, 2^18942621 is an apocalyptic number.

It is an amenable number.

18942621 is a deficient number, since it is larger than the sum of its proper divisors (6314211).

18942621 is an equidigital number, since it uses as much as digits as its factorization.

18942621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6314210.

The product of its digits is 6912, while the sum is 33.

The square root of 18942621 is about 4352.3121441367. The cubic root of 18942621 is about 266.5712795992.

The spelling of 18942621 in words is "eighteen million, nine hundred forty-two thousand, six hundred twenty-one".