22740209 has 2 divisors, whose sum is σ = 22740210. Its totient is φ = 22740208.

The previous prime is 22740197. The next prime is 22740217. The reversal of 22740209 is 90204722.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18447025 + 4293184 = 4295^2 + 2072^2 .

It is a cyclic number.

It is not a de Polignac number, because 22740209 - 2²⁰ = 21691633 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (22740259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11370104 + 11370105.

It is an arithmetic number, because the mean of its divisors is an integer number (11370105).

Almost surely, 2^22740209 is an apocalyptic number.

It is an amenable number.

22740209 is a deficient number, since it is larger than the sum of its proper divisors (1).

22740209 is an equidigital number, since it uses as much as digits as its factorization.

22740209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 22740209 is about 4768.6695209461. The cubic root of 22740209 is about 283.3119004164.

The spelling of 22740209 in words is "twenty-two million, seven hundred forty thousand, two hundred nine".