31420 has 12 divisors (see below), whose sum is σ = 66024. Its totient is φ = 12560.

The previous prime is 31397. The next prime is 31469. The reversal of 31420 is 2413.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a plaindrome in base 13 and base 16.

It is a nialpdrome in base 14.

It is a junction number, because it is equal to n+sod(n) for n = 31397 and 31406.

It is a congruent number.

It is an unprimeable number.

31420 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 766 + ... + 805.

It is an arithmetic number, because the mean of its divisors is an integer number (5502).

2³¹⁴²⁰ is an apocalyptic number.

It is an amenable number.

31420 is an abundant number, since it is smaller than the sum of its proper divisors (34604).

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 (33012).

31420 is a wasteful number, since it uses less digits than its factorization.

31420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1580 (or 1578 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 31420 is about 177.2568757482. The cubic root of 31420 is about 31.5550394091. Note that the first 3 decimals are identical.

Adding to 31420 its reverse (2413), we get a palindrome (33833).

The spelling of 31420 in words is "thirty-one thousand, four hundred twenty".