688049 has 4 divisors (see below), whose sum is σ = 691236. Its totient is φ = 684864.

The previous prime is 688031. The next prime is 688063. The reversal of 688049 is 940886.

688049 is nontrivially palindromic in base 7.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 940886 = 2 ⋅470443.

It can be written as a sum of positive squares in 2 ways, for example, as 351649 + 336400 = 593^2 + 580^2 .

It is a cyclic number.

It is not a de Polignac number, because 688049 - 2¹⁶ = 622513 is a prime.

It is a super-2 number, since 2×688049² = 946822852802, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 688049.

It is not an unprimeable number, because it can be changed into a prime (688249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1244 + ... + 1709.

It is an arithmetic number, because the mean of its divisors is an integer number (172809).

2⁶⁸⁸⁰⁴⁹ is an apocalyptic number.

It is an amenable number.

688049 is a deficient number, since it is larger than the sum of its proper divisors (3187).

688049 is a wasteful number, since it uses less digits than its factorization.

688049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3186.

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 688049 is about 829.4871909801. The cubic root of 688049 is about 88.2821949960.

The spelling of 688049 in words is "six hundred eighty-eight thousand, forty-nine".