211221229 has 2 divisors, whose sum is σ = 211221230. Its totient is φ = 211221228.

The previous prime is 211221169. The next prime is 211221247. The reversal of 211221229 is 922122112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 209960100 + 1261129 = 14490^2 + 1123^2 .

It is a cyclic number.

It is not a de Polignac number, because 211221229 - 2²³ = 202832621 is a prime.

It is a super-2 number, since 2×211221229² = 89228815160540882, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211221629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105610614 + 105610615.

It is an arithmetic number, because the mean of its divisors is an integer number (105610615).

Almost surely, 2^211221229 is an apocalyptic number.

It is an amenable number.

211221229 is a deficient number, since it is larger than the sum of its proper divisors (1).

211221229 is an equidigital number, since it uses as much as digits as its factorization.

211221229 is an evil number, because the sum of its binary digits is even.

The product of its digits is 288, while the sum is 22.

The square root of 211221229 is about 14533.4520675578. The cubic root of 211221229 is about 595.5421737031.

The spelling of 211221229 in words is "two hundred eleven million, two hundred twenty-one thousand, two hundred twenty-nine".