23621021 has 4 divisors (see below), whose sum is σ = 23646912. Its totient is φ = 23595132.

The previous prime is 23621011. The next prime is 23621027. The reversal of 23621021 is 12012632.

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 23621021 - 2¹⁰ = 23619997 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 (23621027) 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, 11525 + ... + 13418.

It is an arithmetic number, because the mean of its divisors is an integer number (5911728).

Almost surely, 2^23621021 is an apocalyptic number.

It is an amenable number.

23621021 is a deficient number, since it is larger than the sum of its proper divisors (25891).

23621021 is an equidigital number, since it uses as much as digits as its factorization.

23621021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25890.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 23621021 is about 4860.1461912169. The cubic root of 23621021 is about 286.9235674041.

Adding to 23621021 its reverse (12012632), we get a palindrome (35633653).

The spelling of 23621021 in words is "twenty-three million, six hundred twenty-one thousand, twenty-one".