199779840 has 480 divisors, whose sum is σ = 804323520. Its totient is φ = 45416448.

The previous prime is 199779791. The next prime is 199779859. The reversal of 199779840 is 48977991.

It is a tau number, because it is divible by the number of its divisors (480).

It is a super-3 number, since 3×199779840³ (a number of 26 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6888946 + ... + 6888974.

It is an arithmetic number, because the mean of its divisors is an integer number (1675674).

Almost surely, 2^199779840 is an apocalyptic number.

199779840 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 199779840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (402161760).

199779840 is an abundant number, since it is smaller than the sum of its proper divisors (604543680).

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

199779840 is a wasteful number, since it uses less digits than its factorization.

199779840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94 (or 75 counting only the distinct ones).

The product of its (nonzero) digits is 1143072, while the sum is 54.

The square root of 199779840 is about 14134.3496489934. The cubic root of 199779840 is about 584.5888849413.

The spelling of 199779840 in words is "one hundred ninety-nine million, seven hundred seventy-nine thousand, eight hundred forty".