684225 has 18 divisors (see below), whose sum is σ = 1225926. Its totient is φ = 364800.

The previous prime is 684221. The next prime is 684239. The reversal of 684225 is 522486.

684225 = 146² + 147² + ... + 172².

It can be written as a sum of positive squares in 3 ways, for example, as 199809 + 484416 = 447^2 + 696^2 .

It is not a de Polignac number, because 684225 - 2² = 684221 is a prime.

It is not an unprimeable number, because it can be changed into a prime (684221) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1296 + ... + 1745.

It is an arithmetic number, because the mean of its divisors is an integer number (68107).

2⁶⁸⁴²²⁵ is an apocalyptic number.

It is an amenable number.

684225 is a deficient number, since it is larger than the sum of its proper divisors (541701).

684225 is a wasteful number, since it uses less digits than its factorization.

684225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3057 (or 3049 counting only the distinct ones).

The product of its digits is 3840, while the sum is 27.

The square root of 684225 is about 827.1789407377. The cubic root of 684225 is about 88.1183411296.

It can be divided in two parts, 684 and 225, that added together give a palindrome (909).

The spelling of 684225 in words is "six hundred eighty-four thousand, two hundred twenty-five".