31320 has 64 divisors (see below), whose sum is σ = 108000. Its totient is φ = 8064.

The previous prime is 31319. The next prime is 31321. The reversal of 31320 is 2313.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (31319) and next prime (31321).

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a nialpdrome in base 15.

It is a congruent number.

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

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1066 + ... + 1094.

2³¹³²⁰ is an apocalyptic number.

31320 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54000).

31320 is an abundant number, since it is smaller than the sum of its proper divisors (76680).

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

31320 is a wasteful number, since it uses less digits than its factorization.

31320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49 (or 39 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 9.

The square root of 31320 is about 176.9745744450. The cubic root of 31320 is about 31.5215272350.

Adding to 31320 its reverse (2313), we get a palindrome (33633).

It can be divided in two parts, 313 and 20, that added together give a palindrome (333).

The spelling of 31320 in words is "thirty-one thousand, three hundred twenty".