12400857 has 20 divisors (see below), whose sum is σ = 21172096. Its totient is φ = 7085880.

The previous prime is 12400849. The next prime is 12400859. The reversal of 12400857 is 75800421.

It is not a de Polignac number, because 12400857 - 2³ = 12400849 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12400857.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12400859) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 10369 + ... + 11502.

Almost surely, 2^12400857 is an apocalyptic number.

It is an amenable number.

12400857 is a deficient number, since it is larger than the sum of its proper divisors (8771239).

12400857 is an equidigital number, since it uses as much as digits as its factorization.

12400857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21890 (or 21881 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 12400857 is about 3521.4850560523. The cubic root of 12400857 is about 231.4642375954.

The spelling of 12400857 in words is "twelve million, four hundred thousand, eight hundred fifty-seven".