199871971939728 has 480 divisors, whose sum is σ = 682702449960960. Its totient is φ = 53798872412160.

The previous prime is 199871971939723. The next prime is 199871971939751. The reversal of 199871971939728 is 827939179178991.

199871971939728 is a `hidden beast` number, since 1 + 9 + 9 + 8 + 7 + 197 + 1 + 9 + 397 + 28 = 666.

It is not an unprimeable number, because it can be changed into a prime (199871971939723) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 133816525 + ... + 135301907.

It is an arithmetic number, because the mean of its divisors is an integer number (1422296770752).

Almost surely, 2^{199871971939728} is an apocalyptic number.

199871971939728 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 199871971939728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (341351224980480).

199871971939728 is an abundant number, since it is smaller than the sum of its proper divisors (482830478021232).

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

199871971939728 is a wasteful number, since it uses less digits than its factorization.

199871971939728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1485707 (or 1485698 counting only the distinct ones).

The product of its digits is 7777461888, while the sum is 90.

The spelling of 199871971939728 in words is "one hundred ninety-nine trillion, eight hundred seventy-one billion, nine hundred seventy-one million, nine hundred thirty-nine thousand, seven hundred twenty-eight".