22217281 has 2 divisors, whose sum is σ = 22217282. Its totient is φ = 22217280.

The previous prime is 22217263. The next prime is 22217291. The reversal of 22217281 is 18271222.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19009600 + 3207681 = 4360^2 + 1791^2 .

It is a cyclic number.

It is not a de Polignac number, because 22217281 - 2⁹ = 22216769 is a prime.

It is a super-2 number, since 2×22217281² = 987215150065922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (22217231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11108640 + 11108641.

It is an arithmetic number, because the mean of its divisors is an integer number (11108641).

Almost surely, 2^22217281 is an apocalyptic number.

It is an amenable number.

22217281 is a deficient number, since it is larger than the sum of its proper divisors (1).

22217281 is an equidigital number, since it uses as much as digits as its factorization.

22217281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 896, while the sum is 25.

The square root of 22217281 is about 4713.5210830121. The cubic root of 22217281 is about 281.1233822814.

The spelling of 22217281 in words is "twenty-two million, two hundred seventeen thousand, two hundred eighty-one".