31504 has 20 divisors (see below), whose sum is σ = 66960. Its totient is φ = 14240.

The previous prime is 31489. The next prime is 31511. The reversal of 31504 is 40513.

It is a plaindrome in base 13.

It is a nialpdrome in base 8.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87 + ... + 265.

It is an arithmetic number, because the mean of its divisors is an integer number (3348).

2³¹⁵⁰⁴ 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 31504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33480).

31504 is an abundant number, since it is smaller than the sum of its proper divisors (35456).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31504 is a wasteful number, since it uses less digits than its factorization.

31504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198 (or 192 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 13.

The square root of 31504 is about 177.4936618587. The cubic root of 31504 is about 31.5831347274.

Subtracting 31504 from its reverse (40513), we obtain a palindrome (9009).

It can be divided in two parts, 31 and 504, that added together give a palindrome (535).

The spelling of 31504 in words is "thirty-one thousand, five hundred four".