863681 has 8 divisors (see below), whose sum is σ = 1063104. Its totient is φ = 683280.

The previous prime is 863671. The next prime is 863689. The reversal of 863681 is 186368.

863681 = T₃₅₈ + T₃₅₉ + ... + T₃₇₀.

863681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a de Polignac number, because none of the positive numbers 2^k-863681 is a prime.

It is a super-2 number, since 2×863681² = 1491889739522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (863689) 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, 4655 + ... + 4836.

It is an arithmetic number, because the mean of its divisors is an integer number (132888).

2⁸⁶³⁶⁸¹ is an apocalyptic number.

It is an amenable number.

863681 is a deficient number, since it is larger than the sum of its proper divisors (199423).

863681 is a wasteful number, since it uses less digits than its factorization.

863681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9511.

The product of its digits is 6912, while the sum is 32.

The square root of 863681 is about 929.3443925693. The cubic root of 863681 is about 95.2323398943.

The spelling of 863681 in words is "eight hundred sixty-three thousand, six hundred eighty-one".