688881 has 4 divisors (see below), whose sum is σ = 918512. Its totient is φ = 459252.

The previous prime is 688871. The next prime is 688889. The reversal of 688881 is 188886.

It is a happy number.

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 688881 - 2¹⁵ = 656113 is a prime.

It is a super-2 number, since 2×688881² = 949114064322, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (688889) 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, 114811 + ... + 114816.

It is an arithmetic number, because the mean of its divisors is an integer number (229628).

2⁶⁸⁸⁸⁸¹ is an apocalyptic number.

It is an amenable number.

688881 is a deficient number, since it is larger than the sum of its proper divisors (229631).

688881 is a wasteful number, since it uses less digits than its factorization.

688881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229630.

The product of its digits is 24576, while the sum is 39.

The square root of 688881 is about 829.9885541379. The cubic root of 688881 is about 88.3177647496.

The spelling of 688881 in words is "six hundred eighty-eight thousand, eight hundred eighty-one".