868681 has 8 divisors (see below), whose sum is σ = 955584. Its totient is φ = 783120.

The previous prime is 868669. The next prime is 868691. The reversal of 868681 is 186868.

868681 = 276² + 277² + ... + 286².

It is the 381-st star number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-868681 is a prime.

It is a super-2 number, since 2×868681² = 1509213359522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 868681.

It is not an unprimeable number, because it can be changed into a prime (868691) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1476 + ... + 1978.

It is an arithmetic number, because the mean of its divisors is an integer number (119448).

2⁸⁶⁸⁶⁸¹ is an apocalyptic number.

It is an amenable number.

868681 is a deficient number, since it is larger than the sum of its proper divisors (86903).

868681 is a wasteful number, since it uses less digits than its factorization.

868681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 671.

The product of its digits is 18432, while the sum is 37.

The square root of 868681 is about 932.0305788975. The cubic root of 868681 is about 95.4157586111.

The spelling of 868681 in words is "eight hundred sixty-eight thousand, six hundred eighty-one".