931681 has 8 divisors (see below), whose sum is σ = 975744. Its totient is φ = 888720.

The previous prime is 931657. The next prime is 931691. The reversal of 931681 is 186139.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 931681 - 2⁹ = 931169 is a prime.

It is a super-2 number, since 2×931681² = 1736058971522, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (931621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1791 + ... + 2251.

It is an arithmetic number, because the mean of its divisors is an integer number (121968).

2⁹³¹⁶⁸¹ is an apocalyptic number.

It is an amenable number.

931681 is a deficient number, since it is larger than the sum of its proper divisors (44063).

931681 is a wasteful number, since it uses less digits than its factorization.

931681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 551.

The product of its digits is 1296, while the sum is 28.

The square root of 931681 is about 965.2362405132. The cubic root of 931681 is about 97.6687762684.

The spelling of 931681 in words is "nine hundred thirty-one thousand, six hundred eighty-one".