678690 has 24 divisors (see below), whose sum is σ = 1764828. Its totient is φ = 180960.

The previous prime is 678659. The next prime is 678719. The reversal of 678690 is 96876.

It can be written as a sum of positive squares in 2 ways, for example, as 622521 + 56169 = 789^2 + 237^2 .

It is a super-2 number, since 2×678690² = 921240232200, which contains 22 as substring.

It is an unprimeable number.

678690 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3681 + ... + 3860.

2⁶⁷⁸⁶⁹⁰ is an apocalyptic number.

678690 is an abundant number, since it is smaller than the sum of its proper divisors (1086138).

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

678690 is a wasteful number, since it uses less digits than its factorization.

678690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7554 (or 7551 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 678690 is about 823.8264380317. The cubic root of 678690 is about 87.8800880553.

The spelling of 678690 in words is "six hundred seventy-eight thousand, six hundred ninety".