199917816 has 64 divisors (see below), whose sum is σ = 579751680. Its totient is φ = 56263680.

The previous prime is 199917803. The next prime is 199917847. The reversal of 199917816 is 618719991.

199917816 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2376 + ... + 20136.

It is an arithmetic number, because the mean of its divisors is an integer number (9058620).

Almost surely, 2^199917816 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 199917816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (289875840).

199917816 is an abundant number, since it is smaller than the sum of its proper divisors (379833864).

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

199917816 is a wasteful number, since it uses less digits than its factorization.

199917816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17844 (or 17840 counting only the distinct ones).

The product of its digits is 244944, while the sum is 51.

The square root of 199917816 is about 14139.2296819876. The cubic root of 199917816 is about 584.7234341769.

The spelling of 199917816 in words is "one hundred ninety-nine million, nine hundred seventeen thousand, eight hundred sixteen".