199981568 has 40 divisors (see below), whose sum is σ = 400852320. Its totient is φ = 99671040.

The previous prime is 199981567. The next prime is 199981571. The reversal of 199981568 is 865189991.

199981568 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (199981567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 316613 + ... + 317243.

It is an arithmetic number, because the mean of its divisors is an integer number (10021308).

Almost surely, 2^199981568 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 199981568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (200426160).

199981568 is an abundant number, since it is smaller than the sum of its proper divisors (200870752).

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

199981568 is an frugal number, since it uses more digits than its factorization.

199981568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1268 (or 1252 counting only the distinct ones).

The product of its digits is 1399680, while the sum is 56.

The square root of 199981568 is about 14141.4839391062. The cubic root of 199981568 is about 584.7855819257.

The spelling of 199981568 in words is "one hundred ninety-nine million, nine hundred eighty-one thousand, five hundred sixty-eight".