23235721 has 2 divisors, whose sum is σ = 23235722. Its totient is φ = 23235720.

The previous prime is 23235713. The next prime is 23235733. The reversal of 23235721 is 12753232.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23145721 + 90000 = 4811^2 + 300^2 .

It is a cyclic number.

It is not a de Polignac number, because 23235721 - 2³ = 23235713 is a prime.

It is not a weakly prime, because it can be changed into another prime (23235701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11617860 + 11617861.

It is an arithmetic number, because the mean of its divisors is an integer number (11617861).

Almost surely, 2^23235721 is an apocalyptic number.

It is an amenable number.

23235721 is a deficient number, since it is larger than the sum of its proper divisors (1).

23235721 is an equidigital number, since it uses as much as digits as its factorization.

23235721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2520, while the sum is 25.

The square root of 23235721 is about 4820.3444897642. The cubic root of 23235721 is about 285.3549327781.

Adding to 23235721 its reverse (12753232), we get a palindrome (35988953).

It can be divided in two parts, 232 and 35721, that added together give a palindrome (35953).

The spelling of 23235721 in words is "twenty-three million, two hundred thirty-five thousand, seven hundred twenty-one".