678005 has 4 divisors (see below), whose sum is σ = 813612. Its totient is φ = 542400.

The previous prime is 677983. The next prime is 678023. The reversal of 678005 is 500876.

678005 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 223729 + 454276 = 473^2 + 674^2 .

It is not a de Polignac number, because 678005 - 2¹⁰ = 676981 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67796 + ... + 67805.

It is an arithmetic number, because the mean of its divisors is an integer number (203403).

2⁶⁷⁸⁰⁰⁵ is an apocalyptic number.

It is an amenable number.

678005 is a deficient number, since it is larger than the sum of its proper divisors (135607).

678005 is a wasteful number, since it uses less digits than its factorization.

678005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135606.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 678005 is about 823.4105901675. The cubic root of 678005 is about 87.8505123903.

The spelling of 678005 in words is "six hundred seventy-eight thousand, five".