678401 has 2 divisors, whose sum is σ = 678402. Its totient is φ = 678400.

The previous prime is 678383. The next prime is 678407. The reversal of 678401 is 104876.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 638401 + 40000 = 799^2 + 200^2 .

It is a cyclic number.

It is not a de Polignac number, because 678401 - 2¹⁸ = 416257 is a prime.

It is a Chen prime.

It is equal to p₅₄₉₂₆ and since 678401 and 54926 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (678407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339200 + 339201.

It is an arithmetic number, because the mean of its divisors is an integer number (339201).

2⁶⁷⁸⁴⁰¹ is an apocalyptic number.

It is an amenable number.

678401 is a deficient number, since it is larger than the sum of its proper divisors (1).

678401 is an equidigital number, since it uses as much as digits as its factorization.

678401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 678401 is about 823.6510183324. The cubic root of 678401 is about 87.8676125750.

The spelling of 678401 in words is "six hundred seventy-eight thousand, four hundred one".