Adding to 345678 its reverse (876543), we get a palindrome (1222221).
345678 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.
It is an alternating number because its digits alternate between odd and even.
It is a straight-line number, since its digits are in arithmetic progression.
It is a plaindrome in base 10.
It is a congruent number.
2345678 is an apocalyptic number.
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
345678 is a wasteful number, since it uses less digits than its factorization.
345678 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 3411.
The square root of 345678 is about 587.9438748724. The cubic root of 345678 is about 70.1817047964.
The spelling of 345678 in words is "three hundred forty-five thousand, six hundred seventy-eight".