678823 has 2 divisors, whose sum is σ = 678824. Its totient is φ = 678822.

The previous prime is 678809. The next prime is 678829. The reversal of 678823 is 328876.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-678823 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (678829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339411 + 339412.

It is an arithmetic number, because the mean of its divisors is an integer number (339412).

2⁶⁷⁸⁸²³ is an apocalyptic number.

678823 is a deficient number, since it is larger than the sum of its proper divisors (1).

678823 is an equidigital number, since it uses as much as digits as its factorization.

678823 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16128, while the sum is 34.

The square root of 678823 is about 823.9071549635. The cubic root of 678823 is about 87.8858281764.

The spelling of 678823 in words is "six hundred seventy-eight thousand, eight hundred twenty-three".