678656 has 36 divisors (see below), whose sum is σ = 1483944. Its totient is φ = 307200.

The previous prime is 678653. The next prime is 678659. The reversal of 678656 is 656876.

It is an interprime number because it is at equal distance from previous prime (678653) and next prime (678659).

It is not an unprimeable number, because it can be changed into a prime (678653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2696 + ... + 2936.

2⁶⁷⁸⁶⁵⁶ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 678656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (741972).

678656 is an abundant number, since it is smaller than the sum of its proper divisors (805288).

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

678656 is a wasteful number, since it uses less digits than its factorization.

678656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268 (or 254 counting only the distinct ones).

The product of its digits is 60480, while the sum is 38.

The square root of 678656 is about 823.8058023588. The cubic root of 678656 is about 87.8786205356.

The spelling of 678656 in words is "six hundred seventy-eight thousand, six hundred fifty-six".