23397821 has 2 divisors, whose sum is σ = 23397822. Its totient is φ = 23397820.

The previous prime is 23397817. The next prime is 23397841. The reversal of 23397821 is 12879332.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18619225 + 4778596 = 4315^2 + 2186^2 .

It is a cyclic number.

It is not a de Polignac number, because 23397821 - 2² = 23397817 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23397811) 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, 11698910 + 11698911.

It is an arithmetic number, because the mean of its divisors is an integer number (11698911).

Almost surely, 2^23397821 is an apocalyptic number.

It is an amenable number.

23397821 is a deficient number, since it is larger than the sum of its proper divisors (1).

23397821 is an equidigital number, since it uses as much as digits as its factorization.

23397821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18144, while the sum is 35.

The square root of 23397821 is about 4837.1294173301. The cubic root of 23397821 is about 286.0169721129.

The spelling of 23397821 in words is "twenty-three million, three hundred ninety-seven thousand, eight hundred twenty-one".