222015221 has 2 divisors, whose sum is σ = 222015222. Its totient is φ = 222015220.

The previous prime is 222015193. The next prime is 222015259. The reversal of 222015221 is 122510222.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 136656100 + 85359121 = 11690^2 + 9239^2 .

It is a cyclic number.

It is not a de Polignac number, because 222015221 - 2²² = 217820917 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 222015221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (222035221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 111007610 + 111007611.

It is an arithmetic number, because the mean of its divisors is an integer number (111007611).

Almost surely, 2^222015221 is an apocalyptic number.

It is an amenable number.

222015221 is a deficient number, since it is larger than the sum of its proper divisors (1).

222015221 is an equidigital number, since it uses as much as digits as its factorization.

222015221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 222015221 is about 14900.1752003122. The cubic root of 222015221 is about 605.5187327583.

Adding to 222015221 its reverse (122510222), we get a palindrome (344525443).

The spelling of 222015221 in words is "two hundred twenty-two million, fifteen thousand, two hundred twenty-one".