221428127 has 2 divisors, whose sum is σ = 221428128. Its totient is φ = 221428126.

The previous prime is 221428013. The next prime is 221428187. The reversal of 221428127 is 721824122.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221428127 - 2¹⁰ = 221427103 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221428127.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221428187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110714063 + 110714064.

It is an arithmetic number, because the mean of its divisors is an integer number (110714064).

Almost surely, 2^221428127 is an apocalyptic number.

221428127 is a deficient number, since it is larger than the sum of its proper divisors (1).

221428127 is an equidigital number, since it uses as much as digits as its factorization.

221428127 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3584, while the sum is 29.

The square root of 221428127 is about 14880.4612495715. The cubic root of 221428127 is about 604.9845197870.

The spelling of 221428127 in words is "two hundred twenty-one million, four hundred twenty-eight thousand, one hundred twenty-seven".