678746 has 4 divisors (see below), whose sum is σ = 1018122. Its totient is φ = 339372.

The previous prime is 678739. The next prime is 678749. The reversal of 678746 is 647876.

678746 is nontrivially palindromic in base 16.

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

It can be written as a sum of positive squares in only one way, i.e., 657721 + 21025 = 811^2 + 145^2 .

It is a super-2 number, since 2×678746² = 921392265032, which contains 22 as substring.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (678749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 169685 + ... + 169688.

2⁶⁷⁸⁷⁴⁶ is an apocalyptic number.

678746 is a deficient number, since it is larger than the sum of its proper divisors (339376).

678746 is a wasteful number, since it uses less digits than its factorization.

678746 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 339375.

The product of its digits is 56448, while the sum is 38.

The square root of 678746 is about 823.8604250721. The cubic root of 678746 is about 87.8825050398.

The spelling of 678746 in words is "six hundred seventy-eight thousand, seven hundred forty-six".