209040 has 80 divisors (see below), whose sum is σ = 708288. Its totient is φ = 50688.

The previous prime is 209039. The next prime is 209063. The reversal of 209040 is 40902.

209040 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3087 + ... + 3153.

2²⁰⁹⁰⁴⁰ is an apocalyptic number.

209040 is a gapful number since it is divisible by the number (20) 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 209040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (354144).

209040 is an abundant number, since it is smaller than the sum of its proper divisors (499248).

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

209040 is a wasteful number, since it uses less digits than its factorization.

209040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96 (or 90 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 209040 is about 457.2089237974. The cubic root of 209040 is about 59.3485071096.

Adding to 209040 its reverse (40902), we get a palindrome (249942).

The spelling of 209040 in words is "two hundred nine thousand, forty".