19819899802857 has 72 divisors (see below), whose sum is σ = 35036135940288. Its totient is φ = 9754153928640.

The previous prime is 19819899802841. The next prime is 19819899802891. The reversal of 19819899802857 is 75820899891891.

It is not a de Polignac number, because 19819899802857 - 2⁴ = 19819899802841 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19819899802857.

It is not an unprimeable number, because it can be changed into a prime (19819899802817) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 9886078 + ... + 11720679.

Almost surely, 2^{19819899802857} is an apocalyptic number.

It is an amenable number.

19819899802857 is a deficient number, since it is larger than the sum of its proper divisors (15216236137431).

19819899802857 is a wasteful number, since it uses less digits than its factorization.

19819899802857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21606827 (or 21606797 counting only the distinct ones).

The product of its (nonzero) digits is 1881169920, while the sum is 84.

The spelling of 19819899802857 in words is "nineteen trillion, eight hundred nineteen billion, eight hundred ninety-nine million, eight hundred two thousand, eight hundred fifty-seven".