688140 has 36 divisors (see below), whose sum is σ = 2087904. Its totient is φ = 183456.

The previous prime is 688139. The next prime is 688147. The reversal of 688140 is 41886.

It is a tau number, because it is divible by the number of its divisors (36).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 688140.

It is not an unprimeable number, because it can be changed into a prime (688147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1732 + ... + 2091.

2⁶⁸⁸¹⁴⁰ is an apocalyptic number.

688140 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

688140 is an abundant number, since it is smaller than the sum of its proper divisors (1399764).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

688140 is a wasteful number, since it uses less digits than its factorization.

688140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3838 (or 3833 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 688140 is about 829.5420423342. The cubic root of 688140 is about 88.2860868340.

It can be divided in two parts, 688 and 140, that added together give a palindrome (828).

The spelling of 688140 in words is "six hundred eighty-eight thousand, one hundred forty".