68681 has 4 divisors (see below), whose sum is σ = 69252. Its totient is φ = 68112.

The previous prime is 68669. The next prime is 68683. The reversal of 68681 is 18686.

68681 is nontrivially palindromic in base 13.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 18686 = 2 ⋅9343.

It can be written as a sum of positive squares in 2 ways, for example, as 55225 + 13456 = 235^2 + 116^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68681 is a prime.

It is a super-2 number, since 2×68681² = 9434159522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 68681.

It is not an unprimeable number, because it can be changed into a prime (68683) 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, 26 + ... + 371.

It is an arithmetic number, because the mean of its divisors is an integer number (17313).

2⁶⁸⁶⁸¹ is an apocalyptic number.

It is an amenable number.

68681 is a deficient number, since it is larger than the sum of its proper divisors (571).

68681 is a wasteful number, since it uses less digits than its factorization.

68681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 570.

The product of its digits is 2304, while the sum is 29.

The square root of 68681 is about 262.0706011746. The cubic root of 68681 is about 40.9523539322.

It can be divided in two parts, 686 and 81, that added together give a palindrome (767).

The spelling of 68681 in words is "sixty-eight thousand, six hundred eighty-one".