19999386857 has 8 divisors (see below), whose sum is σ = 22096509696. Its totient is φ = 18004562752.

The previous prime is 19999386851. The next prime is 19999386863. The reversal of 19999386857 is 75868399991.

It is an interprime number because it is at equal distance from previous prime (19999386851) and next prime (19999386863).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19999386857 - 2²⁶ = 19932277993 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19999386851) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25574273 + ... + 25575054.

It is an arithmetic number, because the mean of its divisors is an integer number (2762063712).

Almost surely, 2^19999386857 is an apocalyptic number.

19999386857 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

19999386857 is a deficient number, since it is larger than the sum of its proper divisors (2097122839).

19999386857 is a wasteful number, since it uses less digits than its factorization.

19999386857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51149367.

The product of its digits is 264539520, while the sum is 74.

The spelling of 19999386857 in words is "nineteen billion, nine hundred ninety-nine million, three hundred eighty-six thousand, eight hundred fifty-seven".