127899221 has 2 divisors, whose sum is σ = 127899222. Its totient is φ = 127899220.

The previous prime is 127899217. The next prime is 127899223. The reversal of 127899221 is 122998721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 118504996 + 9394225 = 10886^2 + 3065^2 .

It is a cyclic number.

It is not a de Polignac number, because 127899221 - 2² = 127899217 is a prime.

Together with 127899223, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (127899223) 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, 63949610 + 63949611.

It is an arithmetic number, because the mean of its divisors is an integer number (63949611).

Almost surely, 2^127899221 is an apocalyptic number.

It is an amenable number.

127899221 is a deficient number, since it is larger than the sum of its proper divisors (1).

127899221 is an equidigital number, since it uses as much as digits as its factorization.

127899221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36288, while the sum is 41.

The square root of 127899221 is about 11309.2537773277. The cubic root of 127899221 is about 503.8361210812.

The spelling of 127899221 in words is "one hundred twenty-seven million, eight hundred ninety-nine thousand, two hundred twenty-one".