Adding to 31000 its reverse (13), we get a palindrome (31013).
It is a happy number.
31000 is nontrivially palindromic in base 9.
31000 is an undulating number in base 9.
It is a plaindrome in base 13.
It is a nialpdrome in base 8 and base 10.
It is a congruent number.
It is an unprimeable number.
231000 is an apocalyptic number.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 31000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37440).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
31000 is a wasteful number, since it uses less digits than its factorization.
31000 is an odious number, because the sum of its binary digits is odd.
The square root of 31000 is about 176.0681686166. The cubic root of 31000 is about 31.4138065239.
The spelling of 31000 in words is "thirty-one thousand".