1287857 has 2 divisors, whose sum is σ = 1287858. Its totient is φ = 1287856.

The previous prime is 1287841. The next prime is 1287883. The reversal of 1287857 is 7587821.

1287857 is nontrivially palindromic in base 4.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1008016 + 279841 = 1004^2 + 529^2 .

It is a cyclic number.

It is not a de Polignac number, because 1287857 - 2⁴ = 1287841 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 1287857.

It is not a weakly prime, because it can be changed into another prime (1287817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 643928 + 643929.

It is an arithmetic number, because the mean of its divisors is an integer number (643929).

2^1287857 is an apocalyptic number.

It is an amenable number.

1287857 is a deficient number, since it is larger than the sum of its proper divisors (1).

1287857 is an equidigital number, since it uses as much as digits as its factorization.

1287857 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 1287857 is about 1134.8378738833. The cubic root of 1287857 is about 108.7984097681.

The spelling of 1287857 in words is "one million, two hundred eighty-seven thousand, eight hundred fifty-seven".