208981 has 8 divisors (see below), whose sum is σ = 233280. Its totient is φ = 186048.

The previous prime is 208963. The next prime is 208991. The reversal of 208981 is 189802.

208981 is a nontrivial binomial coefficient, being equal to C(647, 2).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 208981 - 2⁹ = 208469 is a prime.

It is a super-2 number, since 2×208981² = 87346116722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (208931) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1 + ... + 646.

It is an arithmetic number, because the mean of its divisors is an integer number (29160).

2²⁰⁸⁹⁸¹ is an apocalyptic number.

208981 is the 646-th triangular number.

208981 is the 216-th centered nonagonal number.

It is an amenable number.

208981 is a deficient number, since it is larger than the sum of its proper divisors (24299).

208981 is a wasteful number, since it uses less digits than its factorization.

208981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 683.

The product of its (nonzero) digits is 1152, while the sum is 28.

The square root of 208981 is about 457.1443973188. The cubic root of 208981 is about 59.3429230246.

The spelling of 208981 in words is "two hundred eight thousand, nine hundred eighty-one".