22543621 has 4 divisors (see below), whose sum is σ = 22553152. Its totient is φ = 22534092.

The previous prime is 22543607. The next prime is 22543627. The reversal of 22543621 is 12634522.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 12634522 = 2 ⋅6317261.

It is a cyclic number.

It is not a de Polignac number, because 22543621 - 2⁵ = 22543589 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 (22543627) 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, 1780 + ... + 6946.

It is an arithmetic number, because the mean of its divisors is an integer number (5638288).

Almost surely, 2^22543621 is an apocalyptic number.

It is an amenable number.

22543621 is a deficient number, since it is larger than the sum of its proper divisors (9531).

22543621 is an equidigital number, since it uses as much as digits as its factorization.

22543621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9530.

The product of its digits is 2880, while the sum is 25.

The square root of 22543621 is about 4748.0123209613. The cubic root of 22543621 is about 282.4931305924.

Subtracting from 22543621 its reverse (12634522), we obtain a palindrome (9909099).

The spelling of 22543621 in words is "twenty-two million, five hundred forty-three thousand, six hundred twenty-one".