689931 has 32 divisors (see below), whose sum is σ = 1175040. Its totient is φ = 396000.

The previous prime is 689929. The next prime is 689951. The reversal of 689931 is 139986.

689931 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 689931 - 2¹ = 689929 is a prime.

It is a super-2 number, since 2×689931² = 952009569522, which contains 22 as substring.

Its product of digits (11664) is a multiple of the sum of its prime factors (144).

689931 is strictly pandigital in base 7.

It is not an unprimeable number, because it can be changed into a prime (689921) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6781 + ... + 6881.

It is an arithmetic number, because the mean of its divisors is an integer number (36720).

2⁶⁸⁹⁹³¹ is an apocalyptic number.

689931 is a deficient number, since it is larger than the sum of its proper divisors (485109).

689931 is a wasteful number, since it uses less digits than its factorization.

689931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144 (or 138 counting only the distinct ones).

The product of its digits is 11664, while the sum is 36.

The square root of 689931 is about 830.6208521341. The cubic root of 689931 is about 88.3626136072.

Subtracting from 689931 its reverse (139986), we obtain a palindrome (549945).

It can be divided in two parts, 68 and 9931, that added together give a palindrome (9999).

The spelling of 689931 in words is "six hundred eighty-nine thousand, nine hundred thirty-one".