228333221 has 2 divisors, whose sum is σ = 228333222. Its totient is φ = 228333220.

The previous prime is 228333151. The next prime is 228333227. The reversal of 228333221 is 122333822.

228333221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 154132225 + 74200996 = 12415^2 + 8614^2 .

It is a cyclic number.

It is not a de Polignac number, because 228333221 - 2¹⁰ = 228332197 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 (228333227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 114166610 + 114166611.

It is an arithmetic number, because the mean of its divisors is an integer number (114166611).

Almost surely, 2^228333221 is an apocalyptic number.

It is an amenable number.

228333221 is a deficient number, since it is larger than the sum of its proper divisors (1).

228333221 is an equidigital number, since it uses as much as digits as its factorization.

228333221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 26.

The square root of 228333221 is about 15110.6988918448. The cubic root of 228333221 is about 611.2089443725.

The spelling of 228333221 in words is "two hundred twenty-eight million, three hundred thirty-three thousand, two hundred twenty-one".