199999980 has 72 divisors (see below), whose sum is σ = 609336000. Its totient is φ = 53098752.

The previous prime is 199999963. The next prime is 199999991. The reversal of 199999980 is 89999991.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40696 + ... + 45344.

It is an arithmetic number, because the mean of its divisors is an integer number (8463000).

Almost surely, 2^199999980 is an apocalyptic number.

199999980 is a gapful number since it is divisible by the number (10) 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 199999980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (304668000).

199999980 is an abundant number, since it is smaller than the sum of its proper divisors (409336020).

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

199999980 is a wasteful number, since it uses less digits than its factorization.

199999980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4903 (or 4898 counting only the distinct ones).

The product of its (nonzero) digits is 4251528, while the sum is 63.

The square root of 199999980 is about 14142.1349166242. The cubic root of 199999980 is about 584.8035281491.

It can be divided in two parts, 19 and 9999980, that added together give a palindrome (9999999).

The spelling of 199999980 in words is "one hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred eighty".