210864 has 40 divisors (see below), whose sum is σ = 571392. Its totient is φ = 66880.

The previous prime is 210857. The next prime is 210869. The reversal of 210864 is 468012.

It is a hoax number, since the sum of its digits (21) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 210864.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210869) 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, 1009 + ... + 1199.

2²¹⁰⁸⁶⁴ is an apocalyptic number.

210864 is a gapful number since it is divisible by the number (24) 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 210864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (285696).

210864 is an abundant number, since it is smaller than the sum of its proper divisors (360528).

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

210864 is a wasteful number, since it uses less digits than its factorization.

210864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225 (or 219 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 210864 is about 459.1993031354. The cubic root of 210864 is about 59.5206246321.

Adding to 210864 its reverse (468012), we get a palindrome (678876).

The spelling of 210864 in words is "two hundred ten thousand, eight hundred sixty-four".