688537 has 4 divisors (see below), whose sum is σ = 691636. Its totient is φ = 685440.

The previous prime is 688531. The next prime is 688543. The reversal of 688537 is 735886.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (688531) and next prime (688543).

It can be written as a sum of positive squares in 2 ways, for example, as 491401 + 197136 = 701^2 + 444^2 .

It is a cyclic number.

It is not a de Polignac number, because 688537 - 2¹⁹ = 164249 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 688496 and 688505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688531) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1188 + ... + 1669.

It is an arithmetic number, because the mean of its divisors is an integer number (172909).

2⁶⁸⁸⁵³⁷ is an apocalyptic number.

It is an amenable number.

688537 is a deficient number, since it is larger than the sum of its proper divisors (3099).

688537 is a wasteful number, since it uses less digits than its factorization.

688537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3098.

The product of its digits is 40320, while the sum is 37.

The square root of 688537 is about 829.7812964872. The cubic root of 688537 is about 88.3030614992.

It can be divided in two parts, 688 and 537, that added together give a triangular number (1225 = T₄₉).

The spelling of 688537 in words is "six hundred eighty-eight thousand, five hundred thirty-seven".