210989 has 4 divisors (see below), whose sum is σ = 213180. Its totient is φ = 208800.

The previous prime is 210967. The next prime is 211007. The reversal of 210989 is 989012.

210989 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 195364 + 15625 = 442^2 + 125^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-210989 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210929) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 944 + ... + 1145.

It is an arithmetic number, because the mean of its divisors is an integer number (53295).

2²¹⁰⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

210989 is a deficient number, since it is larger than the sum of its proper divisors (2191).

210989 is a wasteful number, since it uses less digits than its factorization.

210989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2190.

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 210989 is about 459.3353894487. The cubic root of 210989 is about 59.5323835674.

It can be divided in two parts, 210 and 989, that multiplied together give a triangular number (207690 = T₆₄₄).

The spelling of 210989 in words is "two hundred ten thousand, nine hundred eighty-nine".