23321621 has 2 divisors, whose sum is σ = 23321622. Its totient is φ = 23321620.

The previous prime is 23321593. The next prime is 23321653. The reversal of 23321621 is 12612332.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20884900 + 2436721 = 4570^2 + 1561^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23321621 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 23321593 and 23321602.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23321681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11660810 + 11660811.

It is an arithmetic number, because the mean of its divisors is an integer number (11660811).

It is a self-describing number.

Almost surely, 2^23321621 is an apocalyptic number.

It is an amenable number.

23321621 is a deficient number, since it is larger than the sum of its proper divisors (1).

23321621 is an equidigital number, since it uses as much as digits as its factorization.

23321621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432, while the sum is 20.

The square root of 23321621 is about 4829.2464215445. The cubic root of 23321621 is about 285.7061426608.

Adding to 23321621 its reverse (12612332), we get a palindrome (35933953).

The spelling of 23321621 in words is "twenty-three million, three hundred twenty-one thousand, six hundred twenty-one".