22720889 has 2 divisors, whose sum is σ = 22720890. Its totient is φ = 22720888.

The previous prime is 22720843. The next prime is 22720909. The reversal of 22720889 is 98802722.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13017664 + 9703225 = 3608^2 + 3115^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22720889 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (22720829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11360444 + 11360445.

It is an arithmetic number, because the mean of its divisors is an integer number (11360445).

Almost surely, 2^22720889 is an apocalyptic number.

It is an amenable number.

22720889 is a deficient number, since it is larger than the sum of its proper divisors (1).

22720889 is an equidigital number, since it uses as much as digits as its factorization.

22720889 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 22720889 is about 4766.6433682414. The cubic root of 22720889 is about 283.2316440922.

The spelling of 22720889 in words is "twenty-two million, seven hundred twenty thousand, eight hundred eighty-nine".