1277641217 has 2 divisors, whose sum is σ = 1277641218. Its totient is φ = 1277641216.

The previous prime is 1277641199. The next prime is 1277641219. The reversal of 1277641217 is 7121467721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1122987121 + 154654096 = 33511^2 + 12436^2 .

It is a cyclic number.

It is not a de Polignac number, because 1277641217 - 2¹⁶ = 1277575681 is a prime.

Together with 1277641219, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1277641219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 638820608 + 638820609.

It is an arithmetic number, because the mean of its divisors is an integer number (638820609).

Almost surely, 2^1277641217 is an apocalyptic number.

It is an amenable number.

1277641217 is a deficient number, since it is larger than the sum of its proper divisors (1).

1277641217 is an equidigital number, since it uses as much as digits as its factorization.

1277641217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32928, while the sum is 38.

The square root of 1277641217 is about 35744.1074444446. The cubic root of 1277641217 is about 1085.0996863111.

The spelling of 1277641217 in words is "one billion, two hundred seventy-seven million, six hundred forty-one thousand, two hundred seventeen".