1278857 has 2 divisors, whose sum is σ = 1278858. Its totient is φ = 1278856.

The previous prime is 1278839. The next prime is 1278881. The reversal of 1278857 is 7588721.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 732736 + 546121 = 856^2 + 739^2 .

It is a cyclic number.

It is not a de Polignac number, because 1278857 - 2⁸ = 1278601 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 1278857.

It is not a weakly prime, because it can be changed into another prime (1278817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 639428 + 639429.

It is an arithmetic number, because the mean of its divisors is an integer number (639429).

2^1278857 is an apocalyptic number.

It is an amenable number.

1278857 is a deficient number, since it is larger than the sum of its proper divisors (1).

1278857 is an equidigital number, since it uses as much as digits as its factorization.

1278857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31360, while the sum is 38.

The square root of 1278857 is about 1130.8655976729. The cubic root of 1278857 is about 108.5443765045.

The spelling of 1278857 in words is "one million, two hundred seventy-eight thousand, eight hundred fifty-seven".