678719 has 2 divisors, whose sum is σ = 678720. Its totient is φ = 678718.

The previous prime is 678659. The next prime is 678721. The reversal of 678719 is 917876.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 678719 - 2⁸ = 678463 is a prime.

It is a super-2 number, since 2×678719² = 921318961922, which contains 22 as substring.

Together with 678721, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (678739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339359 + 339360.

It is an arithmetic number, because the mean of its divisors is an integer number (339360).

2⁶⁷⁸⁷¹⁹ is an apocalyptic number.

678719 is a deficient number, since it is larger than the sum of its proper divisors (1).

678719 is an equidigital number, since it uses as much as digits as its factorization.

678719 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21168, while the sum is 38.

The square root of 678719 is about 823.8440386384. The cubic root of 678719 is about 87.8813397246.

The spelling of 678719 in words is "six hundred seventy-eight thousand, seven hundred nineteen".