22156209 has 6 divisors (see below), whose sum is σ = 32003426. Its totient is φ = 14770800.

The previous prime is 22156201. The next prime is 22156213. The reversal of 22156209 is 90265122.

22156209 is a `hidden beast` number, since 22 + 15 + 620 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 15186609 + 6969600 = 3897^2 + 2640^2 .

It is not a de Polignac number, because 22156209 - 2³ = 22156201 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (22156201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1230892 + ... + 1230909.

Almost surely, 2^22156209 is an apocalyptic number.

It is an amenable number.

22156209 is a deficient number, since it is larger than the sum of its proper divisors (9847217).

22156209 is a wasteful number, since it uses less digits than its factorization.

22156209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2461807 (or 2461804 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 22156209 is about 4707.0382407624. The cubic root of 22156209 is about 280.8655571117.

The spelling of 22156209 in words is "twenty-two million, one hundred fifty-six thousand, two hundred nine".