22109921 has 2 divisors, whose sum is σ = 22109922. Its totient is φ = 22109920.

The previous prime is 22109909. The next prime is 22109929. The reversal of 22109921 is 12990122.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21669025 + 440896 = 4655^2 + 664^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22109921 is a prime.

It is not a weakly prime, because it can be changed into another prime (22109929) 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, 11054960 + 11054961.

It is an arithmetic number, because the mean of its divisors is an integer number (11054961).

Almost surely, 2^22109921 is an apocalyptic number.

It is an amenable number.

22109921 is a deficient number, since it is larger than the sum of its proper divisors (1).

22109921 is an equidigital number, since it uses as much as digits as its factorization.

22109921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 22109921 is about 4702.1187777426. The cubic root of 22109921 is about 280.6698291486.

The spelling of 22109921 in words is "twenty-two million, one hundred nine thousand, nine hundred twenty-one".