681407 has 2 divisors, whose sum is σ = 681408. Its totient is φ = 681406.

The previous prime is 681403. The next prime is 681409. The reversal of 681407 is 704186.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 681407 - 2² = 681403 is a prime.

Together with 681409, 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 (681403) 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, 340703 + 340704.

It is an arithmetic number, because the mean of its divisors is an integer number (340704).

2⁶⁸¹⁴⁰⁷ is an apocalyptic number.

681407 is a deficient number, since it is larger than the sum of its proper divisors (1).

681407 is an equidigital number, since it uses as much as digits as its factorization.

681407 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 681407 is about 825.4738033396. The cubic root of 681407 is about 87.9972020460.

The spelling of 681407 in words is "six hundred eighty-one thousand, four hundred seven".