681667 has 4 divisors (see below), whose sum is σ = 779056. Its totient is φ = 584280.

The previous prime is 681647. The next prime is 681673. The reversal of 681667 is 766186.

681667 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 681667 - 2⁷ = 681539 is a prime.

It is a Duffinian number.

It is a zygodrome in base 6.

It is not an unprimeable number, because it can be changed into a prime (681607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48684 + ... + 48697.

It is an arithmetic number, because the mean of its divisors is an integer number (194764).

2⁶⁸¹⁶⁶⁷ is an apocalyptic number.

681667 is a deficient number, since it is larger than the sum of its proper divisors (97389).

681667 is an equidigital number, since it uses as much as digits as its factorization.

681667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97388.

The product of its digits is 12096, while the sum is 34.

The square root of 681667 is about 825.6312736325. The cubic root of 681667 is about 88.0083927946.

The spelling of 681667 in words is "six hundred eighty-one thousand, six hundred sixty-seven".