• 210 can be written using four 4's:

See also 113.

---

210 has 16 divisors (see below), whose sum is σ = 576. Its totient is φ = 48.

The previous prime is 199. The next prime is 211. The reversal of 210 is 12.

210 = T₄ + T₅ + ... + T₁₀.

It is a primorial, being the product of the first 4 primes.

210 is nontrivially palindromic in base 11.

210 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

210 is an esthetic number in base 3 and base 10, because in such bases its adjacent digits differ by 1.

210 is a nontrivial binomial coefficient, being equal to C(21, 2), and to C(10, 4).

It is a Harshad number since it is a multiple of its sum of digits (3).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

210 is an idoneal number.

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

210 is an undulating number in base 11.

210 is strictly pandigital in base 4.

It is a Curzon number.

It is a straight-line number, since its digits are in arithmetic progression.

It is a plaindrome in base 12.

It is a nialpdrome in base 6, base 7, base 8, base 10, base 14, base 15 and base 16.

It is a junction number, because it is equal to n+sod(n) for n = 195 and 204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211) by changing a digit.

210 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27 + ... + 33.

It is an arithmetic number, because the mean of its divisors is an integer number (36).

It is a pronic number, being equal to 14×15.

210 is the 20-th triangular number and also the 12-th pentagonal number.

It is a practical number, because each smaller number is the sum of distinct divisors of 210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (288).

210 is an abundant number, since it is smaller than the sum of its proper divisors (366).

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

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

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

The sum of its prime factors is 17.

The product of its (nonzero) digits is 2, while the sum is 3.

The square root of 210 is about 14.4913767462. The cubic root of 210 is about 5.9439219528.

Adding to 210 its reverse (12), we get a palindrome (222).

The spelling of 210 in words is "two hundred ten", and thus it is an aban number and an iban number.