199999863 has 24 divisors (see below), whose sum is σ = 341546400. Its totient is φ = 110343744.

The previous prime is 199999853. The next prime is 199999889. The reversal of 199999863 is 368999991.

It is not a de Polignac number, because 199999863 - 2⁵ = 199999831 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a self number, because there is not a number n which added to its sum of digits gives 199999863.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199999853) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 52908 + ... + 56561.

It is an arithmetic number, because the mean of its divisors is an integer number (14231100).

Almost surely, 2^199999863 is an apocalyptic number.

199999863 is a deficient number, since it is larger than the sum of its proper divisors (141546537).

199999863 is a wasteful number, since it uses less digits than its factorization.

199999863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109511 (or 109508 counting only the distinct ones).

The product of its digits is 8503056, while the sum is 63.

The square root of 199999863 is about 14142.1307800487. The cubic root of 199999863 is about 584.8034141124.

The spelling of 199999863 in words is "one hundred ninety-nine million, nine hundred ninety-nine thousand, eight hundred sixty-three".