681789 has 16 divisors (see below), whose sum is σ = 975744. Its totient is φ = 422400.

The previous prime is 681787. The next prime is 681809. The reversal of 681789 is 987186.

It is not a de Polignac number, because 681789 - 2¹ = 681787 is a prime.

681789 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681781) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2709 + ... + 2949.

It is an arithmetic number, because the mean of its divisors is an integer number (60984).

2⁶⁸¹⁷⁸⁹ is an apocalyptic number.

681789 is a gapful number since it is divisible by the number (69) formed by its first and last digit.

It is an amenable number.

681789 is a deficient number, since it is larger than the sum of its proper divisors (293955).

681789 is a wasteful number, since it uses less digits than its factorization.

681789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308.

The product of its digits is 24192, while the sum is 39.

The square root of 681789 is about 825.7051531873. The cubic root of 681789 is about 88.0136428573.

The spelling of 681789 in words is "six hundred eighty-one thousand, seven hundred eighty-nine".