22561621 has 2 divisors, whose sum is σ = 22561622. Its totient is φ = 22561620.

The previous prime is 22561613. The next prime is 22561631. The reversal of 22561621 is 12616522.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18404100 + 4157521 = 4290^2 + 2039^2 .

It is a cyclic number.

It is not a de Polignac number, because 22561621 - 2³ = 22561613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22561631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11280810 + 11280811.

It is an arithmetic number, because the mean of its divisors is an integer number (11280811).

Almost surely, 2^22561621 is an apocalyptic number.

It is an amenable number.

22561621 is a deficient number, since it is larger than the sum of its proper divisors (1).

22561621 is an equidigital number, since it uses as much as digits as its factorization.

22561621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1440, while the sum is 25.

The square root of 22561621 is about 4749.9074727830. The cubic root of 22561621 is about 282.5682963286.

The spelling of 22561621 in words is "twenty-two million, five hundred sixty-one thousand, six hundred twenty-one".