127928221 has 2 divisors, whose sum is σ = 127928222. Its totient is φ = 127928220.

The previous prime is 127928201. The next prime is 127928239. The reversal of 127928221 is 122829721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 101002500 + 26925721 = 10050^2 + 5189^2 .

It is a cyclic number.

It is not a de Polignac number, because 127928221 - 2⁵ = 127928189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (127928201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63964110 + 63964111.

It is an arithmetic number, because the mean of its divisors is an integer number (63964111).

Almost surely, 2^127928221 is an apocalyptic number.

It is an amenable number.

127928221 is a deficient number, since it is larger than the sum of its proper divisors (1).

127928221 is an equidigital number, since it uses as much as digits as its factorization.

127928221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8064, while the sum is 34.

The square root of 127928221 is about 11310.5358405338. The cubic root of 127928221 is about 503.8741983090.

The spelling of 127928221 in words is "one hundred twenty-seven million, nine hundred twenty-eight thousand, two hundred twenty-one".