199720 has 16 divisors (see below), whose sum is σ = 449460. Its totient is φ = 79872.

The previous prime is 199697. The next prime is 199721. The reversal of 199720 is 27991.

It can be written as a sum of positive squares in 2 ways, for example, as 195364 + 4356 = 442^2 + 66^2 .

It is not an unprimeable number, because it can be changed into a prime (199721) 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, 2457 + ... + 2536.

2¹⁹⁹⁷²⁰ is an apocalyptic number.

199720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

199720 is an abundant number, since it is smaller than the sum of its proper divisors (249740).

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

199720 is a wasteful number, since it uses less digits than its factorization.

199720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5004 (or 5000 counting only the distinct ones).

The product of its (nonzero) digits is 1134, while the sum is 28.

The square root of 199720 is about 446.9004363390. The cubic root of 199720 is about 58.4530511864.

It can be divided in two parts, 199 and 720, that added together give a palindrome (919).

The spelling of 199720 in words is "one hundred ninety-nine thousand, seven hundred twenty".