199440 has 60 divisors (see below), whose sum is σ = 672204. Its totient is φ = 52992.

The previous prime is 199429. The next prime is 199447. The reversal of 199440 is 44991.

It can be written as a sum of positive squares in 2 ways, for example, as 51984 + 147456 = 228^2 + 384^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a nialpdrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (199447) by changing a digit.

199440 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 582 + ... + 858.

2¹⁹⁹⁴⁴⁰ is an apocalyptic number.

199440 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 199440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (336102).

199440 is an abundant number, since it is smaller than the sum of its proper divisors (472764).

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

199440 is a wasteful number, since it uses less digits than its factorization.

199440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 296 (or 287 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 199440 is about 446.5870575823. The cubic root of 199440 is about 58.4257220775.

Subtracting from 199440 its reverse (44991), we obtain a square (154449 = 393²).

The spelling of 199440 in words is "one hundred ninety-nine thousand, four hundred forty".