221220229 has 2 divisors, whose sum is σ = 221220230. Its totient is φ = 221220228.

The previous prime is 221220163. The next prime is 221220257. The reversal of 221220229 is 922022122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 220968225 + 252004 = 14865^2 + 502^2 .

It is a cyclic number.

It is not a de Polignac number, because 221220229 - 2⁷ = 221220101 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221220289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110610114 + 110610115.

It is an arithmetic number, because the mean of its divisors is an integer number (110610115).

Almost surely, 2^221220229 is an apocalyptic number.

It is an amenable number.

221220229 is a deficient number, since it is larger than the sum of its proper divisors (1).

221220229 is an equidigital number, since it uses as much as digits as its factorization.

221220229 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 221220229 is about 14873.4740057594. The cubic root of 221220229 is about 604.7951213018.

The spelling of 221220229 in words is "two hundred twenty-one million, two hundred twenty thousand, two hundred twenty-nine".