221224425221 has 2 divisors, whose sum is σ = 221224425222. Its totient is φ = 221224425220.

The previous prime is 221224425217. The next prime is 221224425239. The reversal of 221224425221 is 122524422122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 204579813025 + 16644612196 = 452305^2 + 129014^2 .

It is a cyclic number.

It is not a de Polignac number, because 221224425221 - 2² = 221224425217 is a prime.

It is a super-3 number, since 3×221224425221³ (a number of 35 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221224425421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110612212610 + 110612212611.

It is an arithmetic number, because the mean of its divisors is an integer number (110612212611).

Almost surely, 2^221224425221 is an apocalyptic number.

It is an amenable number.

221224425221 is a deficient number, since it is larger than the sum of its proper divisors (1).

221224425221 is an equidigital number, since it uses as much as digits as its factorization.

221224425221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10240, while the sum is 29.

Adding to 221224425221 its reverse (122524422122), we get a palindrome (343748847343).

The spelling of 221224425221 in words is "two hundred twenty-one billion, two hundred twenty-four million, four hundred twenty-five thousand, two hundred twenty-one".