31345 has 4 divisors (see below), whose sum is σ = 37620. Its totient is φ = 25072.

The previous prime is 31337. The next prime is 31357. The reversal of 31345 is 54313.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54313 = 7 ⋅7759.

It can be written as a sum of positive squares in 2 ways, for example, as 10609 + 20736 = 103^2 + 144^2 .

It is a cyclic number.

It is not a de Polignac number, because 31345 - 2³ = 31337 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3130 + ... + 3139.

It is an arithmetic number, because the mean of its divisors is an integer number (9405).

2³¹³⁴⁵ is an apocalyptic number.

It is an amenable number.

31345 is a deficient number, since it is larger than the sum of its proper divisors (6275).

31345 is an equidigital number, since it uses as much as digits as its factorization.

31345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6274.

The product of its digits is 180, while the sum is 16.

The square root of 31345 is about 177.0451919709. The cubic root of 31345 is about 31.5299119582.

Subtracting from 31345 its sum of digits (16), we obtain a square (31329 = 177²).

Adding to 31345 its reverse (54313), we get a palindrome (85658).

The spelling of 31345 in words is "thirty-one thousand, three hundred forty-five".