208688520 has 64 divisors (see below), whose sum is σ = 631955520. Its totient is φ = 55126784.

The previous prime is 208688471. The next prime is 208688521. The reversal of 208688520 is 25886802.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (208688521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4714 + ... + 20966.

It is an arithmetic number, because the mean of its divisors is an integer number (9874305).

Almost surely, 2^208688520 is an apocalyptic number.

208688520 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 208688520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (315977760).

208688520 is an abundant number, since it is smaller than the sum of its proper divisors (423267000).

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

208688520 is a wasteful number, since it uses less digits than its factorization.

208688520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16374 (or 16370 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 39.

The square root of 208688520 is about 14446.0555169915. The cubic root of 208688520 is about 593.1522557588.

The spelling of 208688520 in words is "two hundred eight million, six hundred eighty-eight thousand, five hundred twenty".