678739 has 2 divisors, whose sum is σ = 678740. Its totient is φ = 678738.

The previous prime is 678731. The next prime is 678749. The reversal of 678739 is 937876.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 678739 - 2³ = 678731 is a prime.

It is not a weakly prime, because it can be changed into another prime (678731) 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, 339369 + 339370.

It is an arithmetic number, because the mean of its divisors is an integer number (339370).

2⁶⁷⁸⁷³⁹ is an apocalyptic number.

678739 is a deficient number, since it is larger than the sum of its proper divisors (1).

678739 is an equidigital number, since it uses as much as digits as its factorization.

678739 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 63504, while the sum is 40.

The square root of 678739 is about 823.8561767687. The cubic root of 678739 is about 87.8822029240.

The spelling of 678739 in words is "six hundred seventy-eight thousand, seven hundred thirty-nine".