22312181 has 2 divisors, whose sum is σ = 22312182. Its totient is φ = 22312180.

The previous prime is 22312163. The next prime is 22312183. The reversal of 22312181 is 18121322.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18447025 + 3865156 = 4295^2 + 1966^2 .

It is a cyclic number.

It is not a de Polignac number, because 22312181 - 2²² = 18117877 is a prime.

It is a super-3 number, since 3×22312181³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

Together with 22312183, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22312183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11156090 + 11156091.

It is an arithmetic number, because the mean of its divisors is an integer number (11156091).

Almost surely, 2^22312181 is an apocalyptic number.

It is an amenable number.

22312181 is a deficient number, since it is larger than the sum of its proper divisors (1).

22312181 is an equidigital number, since it uses as much as digits as its factorization.

22312181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 192, while the sum is 20.

The square root of 22312181 is about 4723.5771402614. The cubic root of 22312181 is about 281.5230818579.

The spelling of 22312181 in words is "twenty-two million, three hundred twelve thousand, one hundred eighty-one".