688545 has 48 divisors (see below), whose sum is σ = 1415232. Its totient is φ = 305280.

The previous prime is 688543. The next prime is 688561. The reversal of 688545 is 545886.

It is a happy number.

It is not a de Polignac number, because 688545 - 2¹ = 688543 is a prime.

It is not an unprimeable number, because it can be changed into a prime (688543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6382 + ... + 6488.

It is an arithmetic number, because the mean of its divisors is an integer number (29484).

2⁶⁸⁸⁵⁴⁵ is an apocalyptic number.

688545 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

688545 is an abundant number, since it is smaller than the sum of its proper divisors (726687).

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

688545 is a wasteful number, since it uses less digits than its factorization.

688545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142 (or 139 counting only the distinct ones).

The product of its digits is 38400, while the sum is 36.

The square root of 688545 is about 829.7861170205. The cubic root of 688545 is about 88.3034034909.

The spelling of 688545 in words is "six hundred eighty-eight thousand, five hundred forty-five".