199643904 has 108 divisors (see below), whose sum is σ = 583999416. Its totient is φ = 65581056.

The previous prime is 199643881. The next prime is 199643947. The reversal of 199643904 is 409346991.

It is a super-2 number, since 2×199643904² = 79715376808722432, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 199643904.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 167599 + ... + 168785.

It is an arithmetic number, because the mean of its divisors is an integer number (5407402).

Almost surely, 2^199643904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 199643904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (291999708).

199643904 is an abundant number, since it is smaller than the sum of its proper divisors (384355512).

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

199643904 is a wasteful number, since it uses less digits than its factorization.

199643904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1282 (or 1265 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 45.

The square root of 199643904 is about 14129.5401199048. The cubic root of 199643904 is about 584.4562644439.

The spelling of 199643904 in words is "one hundred ninety-nine million, six hundred forty-three thousand, nine hundred four".