22161215 has 4 divisors (see below), whose sum is σ = 26593464. Its totient is φ = 17728968.

The previous prime is 22161199. The next prime is 22161229. The reversal of 22161215 is 51216122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 22161215 - 2⁴ = 22161199 is a prime.

It is a super-2 number, since 2×22161215² = 982238900552450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2216117 + ... + 2216126.

It is an arithmetic number, because the mean of its divisors is an integer number (6648366).

Almost surely, 2^22161215 is an apocalyptic number.

22161215 is a deficient number, since it is larger than the sum of its proper divisors (4432249).

22161215 is an equidigital number, since it uses as much as digits as its factorization.

22161215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4432248.

The product of its digits is 240, while the sum is 20.

The square root of 22161215 is about 4707.5699676160. The cubic root of 22161215 is about 280.8867085506.

Adding to 22161215 its reverse (51216122), we get a palindrome (73377337).

The spelling of 22161215 in words is "twenty-two million, one hundred sixty-one thousand, two hundred fifteen".