208243840 has 256 divisors, whose sum is σ = 620421120. Its totient is φ = 65286144.

The previous prime is 208243831. The next prime is 208243901. The reversal of 208243840 is 48342802.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4430697 + ... + 4430743.

It is an arithmetic number, because the mean of its divisors is an integer number (2423520).

Almost surely, 2^208243840 is an apocalyptic number.

208243840 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 208243840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (310210560).

208243840 is an abundant number, since it is smaller than the sum of its proper divisors (412177280).

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

208243840 is a wasteful number, since it uses less digits than its factorization.

208243840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139 (or 127 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 31.

The square root of 208243840 is about 14430.6562567334. The cubic root of 208243840 is about 592.7306537273.

The spelling of 208243840 in words is "two hundred eight million, two hundred forty-three thousand, eight hundred forty".