22118209 has 3 divisors (see below), whose sum is σ = 22122913. Its totient is φ = 22113506.

The previous prime is 22118179. The next prime is 22118227. The reversal of 22118209 is 90281122.

The square root of 22118209 is 4703.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 22118209 - 2¹³ = 22110017 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22118269) 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 in 2 ways as a sum of consecutive naturals, for example, 2352 + ... + 7054.

Almost surely, 2^22118209 is an apocalyptic number.

22118209 is the 4703-rd square number.

22118209 is the 2352-nd centered octagonal number.

It is an amenable number.

22118209 is a deficient number, since it is larger than the sum of its proper divisors (4704).

22118209 is an frugal number, since it uses more digits than its factorization.

22118209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9406 (or 4703 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 25.

The cubic root of 22118209 is about 280.7048948693.

Multiplying 22118209 by its sum of digits (25), we get a square (552955225 = 23515²).

Multiplying 22118209 by its product of nonzero digits (576), we get a square (12740088384 = 112872²).

The spelling of 22118209 in words is "twenty-two million, one hundred eighteen thousand, two hundred nine".