23220421 has 4 divisors (see below), whose sum is σ = 26537632. Its totient is φ = 19903212.

The previous prime is 23220403. The next prime is 23220437. The reversal of 23220421 is 12402232.

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 not a de Polignac number, because 23220421 - 2⁵ = 23220389 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 23220395 and 23220404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23220481) 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, 1658595 + ... + 1658608.

It is an arithmetic number, because the mean of its divisors is an integer number (6634408).

Almost surely, 2^23220421 is an apocalyptic number.

It is an amenable number.

23220421 is a deficient number, since it is larger than the sum of its proper divisors (3317211).

23220421 is an equidigital number, since it uses as much as digits as its factorization.

23220421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3317210.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 23220421 is about 4818.7572049233. The cubic root of 23220421 is about 285.2922865749.

Adding to 23220421 its reverse (12402232), we get a palindrome (35622653).

The spelling of 23220421 in words is "twenty-three million, two hundred twenty thousand, four hundred twenty-one".