31224 has 16 divisors (see below), whose sum is σ = 78120.
Its totient is φ = 10400.
The previous prime is 31223. The next prime is 31231. The reversal of 31224 is 42213.
Adding to 31224 its reverse (42213), we get a palindrome (73437).
It is a Harshad number since it is a multiple of its sum of digits (12).
It is a fibodiv number, since the Fibonacci-like sequence with seeds 312 and 24 contains 31224 itself.
It is a nude number because it is divisible by every one of its digits.
It is a plaindrome in base 13.
It is a nialpdrome in base 14.
It is a zygodrome in base 2.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (31223) 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, 627 + ... + 674.
231224 is an apocalyptic number.
It is an amenable number.
31224 is an abundant number, since it is smaller than the sum of its proper divisors (46896).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39060).
31224 is a wasteful number, since it uses less digits than its factorization.
31224 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 1310 (or 1306 counting only the distinct ones).
The product of its digits is 48, while the sum is 12.
The square root of 31224 is about 176.7031408889.
The cubic root of 31224 is about 31.4892883710.
The spelling of 31224 in words is "thirty-one thousand, two hundred twenty-four".