1280711857 has 2 divisors, whose sum is σ = 1280711858. Its totient is φ = 1280711856.

The previous prime is 1280711827. The next prime is 1280711863. The reversal of 1280711857 is 7581170821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1279421361 + 1290496 = 35769^2 + 1136^2 .

It is a cyclic number.

It is not a de Polignac number, because 1280711857 - 2¹⁹ = 1280187569 is a prime.

It is not a weakly prime, because it can be changed into another prime (1280711807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 640355928 + 640355929.

It is an arithmetic number, because the mean of its divisors is an integer number (640355929).

Almost surely, 2^1280711857 is an apocalyptic number.

It is an amenable number.

1280711857 is a deficient number, since it is larger than the sum of its proper divisors (1).

1280711857 is an equidigital number, since it uses as much as digits as its factorization.

1280711857 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31360, while the sum is 40.

The square root of 1280711857 is about 35787.0347612093. The cubic root of 1280711857 is about 1085.9682882096.

The spelling of 1280711857 in words is "one billion, two hundred eighty million, seven hundred eleven thousand, eight hundred fifty-seven".