18265621 has 8 divisors (see below), whose sum is σ = 20613600. Its totient is φ = 16032240.

The previous prime is 18265619. The next prime is 18265661. The reversal of 18265621 is 12656281.

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 18265621 - 2¹ = 18265619 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18265601) 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, 28311 + ... + 28948.

It is an arithmetic number, because the mean of its divisors is an integer number (2576700).

Almost surely, 2^18265621 is an apocalyptic number.

18265621 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18265621 is a deficient number, since it is larger than the sum of its proper divisors (2347979).

18265621 is a wasteful number, since it uses less digits than its factorization.

18265621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57299.

The product of its digits is 5760, while the sum is 31.

The square root of 18265621 is about 4273.8297813554. The cubic root of 18265621 is about 263.3569682716.

It can be divided in two parts, 1826 and 5621, that added together give a palindrome (7447).

The spelling of 18265621 in words is "eighteen million, two hundred sixty-five thousand, six hundred twenty-one".