688261 has 4 divisors (see below), whose sum is σ = 786592. Its totient is φ = 589932.

The previous prime is 688253. The next prime is 688277. The reversal of 688261 is 162886.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 688261 - 2³ = 688253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688201) 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, 49155 + ... + 49168.

It is an arithmetic number, because the mean of its divisors is an integer number (196648).

2⁶⁸⁸²⁶¹ is an apocalyptic number.

It is an amenable number.

688261 is a deficient number, since it is larger than the sum of its proper divisors (98331).

688261 is an equidigital number, since it uses as much as digits as its factorization.

688261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98330.

The product of its digits is 4608, while the sum is 31.

The square root of 688261 is about 829.6149709353. The cubic root of 688261 is about 88.2912611640.

It can be divided in two parts, 688 and 261, that added together give a palindrome (949).

The spelling of 688261 in words is "six hundred eighty-eight thousand, two hundred sixty-one".