684657 has 12 divisors (see below), whose sum is σ = 998400. Its totient is φ = 452088.

The previous prime is 684647. The next prime is 684683. The reversal of 684657 is 756486.

It is a happy number.

684657 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 684657 - 2¹⁴ = 668273 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (684617) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 844 + ... + 1442.

It is an arithmetic number, because the mean of its divisors is an integer number (83200).

2⁶⁸⁴⁶⁵⁷ is an apocalyptic number.

It is an amenable number.

684657 is a deficient number, since it is larger than the sum of its proper divisors (313743).

684657 is a wasteful number, since it uses less digits than its factorization.

684657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 732 (or 729 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The square root of 684657 is about 827.4400280383. The cubic root of 684657 is about 88.1368823573.

It can be divided in two parts, 6846 and 57, that added together give a triangular number (6903 = T₁₁₇).

The spelling of 684657 in words is "six hundred eighty-four thousand, six hundred fifty-seven".