209898240 has 144 divisors (see below), whose sum is σ = 685214208. Its totient is φ = 54734848.

The previous prime is 209898239. The next prime is 209898251. The reversal of 209898240 is 42898902.

It is a junction number, because it is equal to n+sod(n) for n = 209898192 and 209898201.

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, 179899 + ... + 181061.

It is an arithmetic number, because the mean of its divisors is an integer number (4758432).

Almost surely, 2^209898240 is an apocalyptic number.

209898240 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 209898240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (342607104).

209898240 is an abundant number, since it is smaller than the sum of its proper divisors (475315968).

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

209898240 is a wasteful number, since it uses less digits than its factorization.

209898240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1234 (or 1220 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 42.

The square root of 209898240 is about 14487.8652671814. The cubic root of 209898240 is about 594.2961712727.

The spelling of 209898240 in words is "two hundred nine million, eight hundred ninety-eight thousand, two hundred forty".