22720961 has 2 divisors, whose sum is σ = 22720962. Its totient is φ = 22720960.

The previous prime is 22720939. The next prime is 22720963. The reversal of 22720961 is 16902722.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11458225 + 11262736 = 3385^2 + 3356^2 .

It is a cyclic number.

It is not a de Polignac number, because 22720961 - 2¹⁰ = 22719937 is a prime.

Together with 22720963, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (22720963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11360480 + 11360481.

It is an arithmetic number, because the mean of its divisors is an integer number (11360481).

Almost surely, 2^22720961 is an apocalyptic number.

It is an amenable number.

22720961 is a deficient number, since it is larger than the sum of its proper divisors (1).

22720961 is an equidigital number, since it uses as much as digits as its factorization.

22720961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 22720961 is about 4766.6509207199. The cubic root of 22720961 is about 283.2319432685.

The spelling of 22720961 in words is "twenty-two million, seven hundred twenty thousand, nine hundred sixty-one".