209140 has 12 divisors (see below), whose sum is σ = 439236. Its totient is φ = 83648.

The previous prime is 209123. The next prime is 209147. The reversal of 209140 is 41902.

209140 = 111² + 112² + ... + 125².

209140 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 138384 + 70756 = 372^2 + 266^2 .

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209147) by changing a digit.

209140 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 3 ways as a sum of consecutive naturals, for example, 5209 + ... + 5248.

It is an arithmetic number, because the mean of its divisors is an integer number (36603).

2²⁰⁹¹⁴⁰ is an apocalyptic number.

209140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

209140 is an abundant number, since it is smaller than the sum of its proper divisors (230096).

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

209140 is a wasteful number, since it uses less digits than its factorization.

209140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10466 (or 10464 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 209140 is about 457.3182699171. The cubic root of 209140 is about 59.3579692614.

The spelling of 209140 in words is "two hundred nine thousand, one hundred forty".