23210521 has 2 divisors, whose sum is σ = 23210522. Its totient is φ = 23210520.

The previous prime is 23210503. The next prime is 23210531. The reversal of 23210521 is 12501232.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21855625 + 1354896 = 4675^2 + 1164^2 .

It is a cyclic number.

It is not a de Polignac number, because 23210521 - 2⁵ = 23210489 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 23210495 and 23210504.

It is not a weakly prime, because it can be changed into another prime (23210531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11605260 + 11605261.

It is an arithmetic number, because the mean of its divisors is an integer number (11605261).

Almost surely, 2^23210521 is an apocalyptic number.

It is an amenable number.

23210521 is a deficient number, since it is larger than the sum of its proper divisors (1).

23210521 is an equidigital number, since it uses as much as digits as its factorization.

23210521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 23210521 is about 4817.7298595915. The cubic root of 23210521 is about 285.2517361312.

Adding to 23210521 its reverse (12501232), we get a palindrome (35711753).

The spelling of 23210521 in words is "twenty-three million, two hundred ten thousand, five hundred twenty-one".