684690 has 32 divisors (see below), whose sum is σ = 1702080. Its totient is φ = 176064.

The previous prime is 684683. The next prime is 684713. The reversal of 684690 is 96486.

It is a super-2 number, since 2×684690² = 937600792200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 477 + ... + 1263.

It is an arithmetic number, because the mean of its divisors is an integer number (53190).

2⁶⁸⁴⁶⁹⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 684690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (851040).

684690 is an abundant number, since it is smaller than the sum of its proper divisors (1017390).

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

684690 is a wasteful number, since it uses less digits than its factorization.

684690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 826.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 684690 is about 827.4599688202. The cubic root of 684690 is about 88.1382983804.

The spelling of 684690 in words is "six hundred eighty-four thousand, six hundred ninety".