18285621 has 16 divisors (see below), whose sum is σ = 26036736. Its totient is φ = 11387376.

The previous prime is 18285611. The next prime is 18285643. The reversal of 18285621 is 12658281.

It is not a de Polignac number, because 18285621 - 2¹⁵ = 18252853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18285611) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 115 + ... + 6048.

It is an arithmetic number, because the mean of its divisors is an integer number (1627296).

Almost surely, 2^18285621 is an apocalyptic number.

It is an amenable number.

18285621 is a deficient number, since it is larger than the sum of its proper divisors (7751115).

18285621 is a wasteful number, since it uses less digits than its factorization.

18285621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6232.

The product of its digits is 7680, while the sum is 33.

The square root of 18285621 is about 4276.1689629854. The cubic root of 18285621 is about 263.4530543944.

The spelling of 18285621 in words is "eighteen million, two hundred eighty-five thousand, six hundred twenty-one".