31328 has 24 divisors (see below), whose sum is σ = 68040. Its totient is φ = 14080.

The previous prime is 31327. The next prime is 31333. The reversal of 31328 is 82313.

It is a Cunningham number, because it is equal to 177²-1.

It is a plaindrome in base 13.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 31328.

It is not an unprimeable number, because it can be changed into a prime (31321) by changing a digit.

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, 308 + ... + 396.

It is an arithmetic number, because the mean of its divisors is an integer number (2835).

2³¹³²⁸ 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 31328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34020).

31328 is an abundant number, since it is smaller than the sum of its proper divisors (36712).

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

31328 is a wasteful number, since it uses less digits than its factorization.

31328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110 (or 102 counting only the distinct ones).

The product of its digits is 144, while the sum is 17.

The square root of 31328 is about 176.9971751187. The cubic root of 31328 is about 31.5242108317.

It can be divided in two parts, 3 and 1328, that added together give a palindrome (1331).

The spelling of 31328 in words is "thirty-one thousand, three hundred twenty-eight".