684669 has 4 divisors (see below), whose sum is σ = 912896. Its totient is φ = 456444.

The previous prime is 684647. The next prime is 684683. The reversal of 684669 is 966486.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 684669 - 2⁵ = 684637 is a prime.

It is a super-2 number, since 2×684669² = 937543279122, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (684269) 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, 114109 + ... + 114114.

It is an arithmetic number, because the mean of its divisors is an integer number (228224).

2⁶⁸⁴⁶⁶⁹ is an apocalyptic number.

It is an amenable number.

684669 is a deficient number, since it is larger than the sum of its proper divisors (228227).

684669 is a wasteful number, since it uses less digits than its factorization.

684669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228226.

The product of its digits is 62208, while the sum is 39.

The square root of 684669 is about 827.4472792873. The cubic root of 684669 is about 88.1373972801.

The spelling of 684669 in words is "six hundred eighty-four thousand, six hundred sixty-nine".