199934421568 has 112 divisors (see below), whose sum is σ = 458266783744. Its totient is φ = 84774574080.

The previous prime is 199934421563. The next prime is 199934421637. The reversal of 199934421568 is 865124439991.

It is a tau number, because it is divible by the number of its divisors (112).

It is not an unprimeable number, because it can be changed into a prime (199934421563) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21217498 + ... + 21226918.

It is an arithmetic number, because the mean of its divisors is an integer number (4091667712).

Almost surely, 2^199934421568 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 199934421568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (229133391872).

199934421568 is an abundant number, since it is smaller than the sum of its proper divisors (258332362176).

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

199934421568 is a wasteful number, since it uses less digits than its factorization.

199934421568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9940 (or 9930 counting only the distinct ones).

The product of its digits is 16796160, while the sum is 61.

The spelling of 199934421568 in words is "one hundred ninety-nine billion, nine hundred thirty-four million, four hundred twenty-one thousand, five hundred sixty-eight".