23221381 has 2 divisors, whose sum is σ = 23221382. Its totient is φ = 23221380.

The previous prime is 23221379. The next prime is 23221391. The reversal of 23221381 is 18312232.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14753281 + 8468100 = 3841^2 + 2910^2 .

It is a cyclic number.

It is not a de Polignac number, because 23221381 - 2¹ = 23221379 is a prime.

It is a super-2 number, since 2×23221381² = 1078465071094322, which contains 22 as substring.

Together with 23221379, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23221301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11610690 + 11610691.

It is an arithmetic number, because the mean of its divisors is an integer number (11610691).

Almost surely, 2^23221381 is an apocalyptic number.

It is an amenable number.

23221381 is a deficient number, since it is larger than the sum of its proper divisors (1).

23221381 is an equidigital number, since it uses as much as digits as its factorization.

23221381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 22.

The square root of 23221381 is about 4818.8568146398. The cubic root of 23221381 is about 285.2962181261.

The spelling of 23221381 in words is "twenty-three million, two hundred twenty-one thousand, three hundred eighty-one".