129286857 has 16 divisors (see below), whose sum is σ = 197188992. Its totient is φ = 73810560.

The previous prime is 129286823. The next prime is 129286907. The reversal of 129286857 is 758682921.

It is not a de Polignac number, because 129286857 - 2⁶ = 129286793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (129286057) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29023 + ... + 33179.

It is an arithmetic number, because the mean of its divisors is an integer number (12324312).

Almost surely, 2^129286857 is an apocalyptic number.

It is an amenable number.

129286857 is a deficient number, since it is larger than the sum of its proper divisors (67902135).

129286857 is a wasteful number, since it uses less digits than its factorization.

129286857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5648.

The product of its digits is 483840, while the sum is 48.

The square root of 129286857 is about 11370.4378543660. The cubic root of 129286857 is about 505.6516855364.

The spelling of 129286857 in words is "one hundred twenty-nine million, two hundred eighty-six thousand, eight hundred fifty-seven".