22619981 has 2 divisors, whose sum is σ = 22619982. Its totient is φ = 22619980.

The previous prime is 22619977. The next prime is 22620011. The reversal of 22619981 is 18991622.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12187081 + 10432900 = 3491^2 + 3230^2 .

It is a cyclic number.

It is not a de Polignac number, because 22619981 - 2² = 22619977 is a prime.

It is a super-2 number, since 2×22619981² = 1023327080880722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22619921) 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, 11309990 + 11309991.

It is an arithmetic number, because the mean of its divisors is an integer number (11309991).

Almost surely, 2^22619981 is an apocalyptic number.

It is an amenable number.

22619981 is a deficient number, since it is larger than the sum of its proper divisors (1).

22619981 is an equidigital number, since it uses as much as digits as its factorization.

22619981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 38.

The square root of 22619981 is about 4756.0467827808. The cubic root of 22619981 is about 282.8117257551.

The spelling of 22619981 in words is "twenty-two million, six hundred nineteen thousand, nine hundred eighty-one".