22212161 has 4 divisors (see below), whose sum is σ = 22233300. Its totient is φ = 22191024.

The previous prime is 22212133. The next prime is 22212187. The reversal of 22212161 is 16121222.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2356225 + 19855936 = 1535^2 + 4456^2 .

It is a cyclic number.

It is not a de Polignac number, because 22212161 - 2⁶ = 22212097 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (22212101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8906 + ... + 11123.

It is an arithmetic number, because the mean of its divisors is an integer number (5558325).

Almost surely, 2^22212161 is an apocalyptic number.

It is an amenable number.

22212161 is a deficient number, since it is larger than the sum of its proper divisors (21139).

22212161 is a wasteful number, since it uses less digits than its factorization.

22212161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21138.

The product of its digits is 96, while the sum is 17.

The square root of 22212161 is about 4712.9779333241. The cubic root of 22212161 is about 281.1017855448.

Adding to 22212161 its reverse (16121222), we get a palindrome (38333383).

The spelling of 22212161 in words is "twenty-two million, two hundred twelve thousand, one hundred sixty-one".