22521217 has 2 divisors, whose sum is σ = 22521218. Its totient is φ = 22521216.

The previous prime is 22521211. The next prime is 22521223. The reversal of 22521217 is 71212522.

It is a balanced prime because it is at equal distance from previous prime (22521211) and next prime (22521223).

It can be written as a sum of positive squares in only one way, i.e., 12383361 + 10137856 = 3519^2 + 3184^2 .

It is a cyclic number.

It is not a de Polignac number, because 22521217 - 2⁷ = 22521089 is a prime.

It is a super-2 number, since 2×22521217² = 1014410430322178, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (22521211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11260608 + 11260609.

It is an arithmetic number, because the mean of its divisors is an integer number (11260609).

Almost surely, 2^22521217 is an apocalyptic number.

It is an amenable number.

22521217 is a deficient number, since it is larger than the sum of its proper divisors (1).

22521217 is an equidigital number, since it uses as much as digits as its factorization.

22521217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 560, while the sum is 22.

The square root of 22521217 is about 4745.6524314366. The cubic root of 22521217 is about 282.3995183927.

Adding to 22521217 its reverse (71212522), we get a palindrome (93733739).

The spelling of 22521217 in words is "twenty-two million, five hundred twenty-one thousand, two hundred seventeen".