1285406857 has 12 divisors (see below), whose sum is σ = 1499364480. Its totient is φ = 1098759816.

The previous prime is 1285406833. The next prime is 1285406879. The reversal of 1285406857 is 7586045821.

It is not a de Polignac number, because 1285406857 - 2²⁷ = 1151189129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1285406357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17757 + ... + 53722.

It is an arithmetic number, because the mean of its divisors is an integer number (124947040).

Almost surely, 2^1285406857 is an apocalyptic number.

It is an amenable number.

1285406857 is a deficient number, since it is larger than the sum of its proper divisors (213957623).

1285406857 is an equidigital number, since it uses as much as digits as its factorization.

1285406857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71860 (or 71853 counting only the distinct ones).

The product of its (nonzero) digits is 537600, while the sum is 46.

The square root of 1285406857 is about 35852.5711351362. The cubic root of 1285406857 is about 1087.2936978109.

The spelling of 1285406857 in words is "one billion, two hundred eighty-five million, four hundred six thousand, eight hundred fifty-seven".