688958 has 4 divisors (see below), whose sum is σ = 1033440. Its totient is φ = 344478.

The previous prime is 688957. The next prime is 688969. The reversal of 688958 is 859886.

688958 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 859886 = 2 ⋅429943.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172238 + ... + 172241.

It is an arithmetic number, because the mean of its divisors is an integer number (258360).

2⁶⁸⁸⁹⁵⁸ is an apocalyptic number.

688958 is a deficient number, since it is larger than the sum of its proper divisors (344482).

688958 is a wasteful number, since it uses less digits than its factorization.

688958 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344481.

The product of its digits is 138240, while the sum is 44.

The square root of 688958 is about 830.0349390237. The cubic root of 688958 is about 88.3210552137.

The spelling of 688958 in words is "six hundred eighty-eight thousand, nine hundred fifty-eight".