208021680 has 120 divisors (see below), whose sum is σ = 701606880. Its totient is φ = 55234560.

The previous prime is 208021679. The next prime is 208021739. The reversal of 208021680 is 86120802.

It is a tau number, because it is divible by the number of its divisors (120).

208021680 is a modest number, since divided by 21680 gives 2080 as remainder.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 223456 + ... + 224384.

It is an arithmetic number, because the mean of its divisors is an integer number (5846724).

Almost surely, 2^208021680 is an apocalyptic number.

208021680 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 208021680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (350803440).

208021680 is an abundant number, since it is smaller than the sum of its proper divisors (493585200).

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

208021680 is a wasteful number, since it uses less digits than its factorization.

208021680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1259 (or 1250 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 208021680 is about 14422.9567010374. The cubic root of 208021680 is about 592.5197985159.

The spelling of 208021680 in words is "two hundred eight million, twenty-one thousand, six hundred eighty".