688145 has 8 divisors (see below), whose sum is σ = 830760. Its totient is φ = 547200.

The previous prime is 688139. The next prime is 688147. The reversal of 688145 is 541886.

It can be written as a sum of positive squares in 4 ways, for example, as 332929 + 355216 = 577^2 + 596^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 688145 - 2¹⁰ = 687121 is a prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 688145.

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 7 ways as a sum of consecutive naturals, for example, 845 + ... + 1445.

It is an arithmetic number, because the mean of its divisors is an integer number (103845).

2⁶⁸⁸¹⁴⁵ is an apocalyptic number.

It is an amenable number.

688145 is a deficient number, since it is larger than the sum of its proper divisors (142615).

688145 is a wasteful number, since it uses less digits than its factorization.

688145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 835.

The product of its digits is 7680, while the sum is 32.

The square root of 688145 is about 829.5450560398. The cubic root of 688145 is about 88.2863006613.

The spelling of 688145 in words is "six hundred eighty-eight thousand, one hundred forty-five".