199945878 has 16 divisors (see below), whose sum is σ = 436245696. Its totient is φ = 60589640.

The previous prime is 199945853. The next prime is 199945903. The reversal of 199945878 is 878549991.

It is an interprime number because it is at equal distance from previous prime (199945853) and next prime (199945903).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1514676 + ... + 1514807.

It is an arithmetic number, because the mean of its divisors is an integer number (27265356).

Almost surely, 2^199945878 is an apocalyptic number.

199945878 is an abundant number, since it is smaller than the sum of its proper divisors (236299818).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

199945878 is a wasteful number, since it uses less digits than its factorization.

199945878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3029499.

The product of its digits is 6531840, while the sum is 60.

The square root of 199945878 is about 14140.2219925997. The cubic root of 199945878 is about 584.7507916542.

The spelling of 199945878 in words is "one hundred ninety-nine million, nine hundred forty-five thousand, eight hundred seventy-eight".