20140 has 24 divisors (see below), whose sum is σ = 45360. Its totient is φ = 7488.

The previous prime is 20129. The next prime is 20143. The reversal of 20140 is 4102.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (20143) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 354 + ... + 406.

It is an arithmetic number, because the mean of its divisors is an integer number (1890).

2²⁰¹⁴⁰ is an apocalyptic number.

20140 is a gapful number since it is divisible by the number (20) 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 20140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22680).

20140 is an abundant number, since it is smaller than the sum of its proper divisors (25220).

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

20140 is a wasteful number, since it uses less digits than its factorization.

20140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81 (or 79 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 7.

The square root of 20140 is about 141.9154677969. The cubic root of 20140 is about 27.2073653641.

Adding to 20140 its reverse (4102), we get a palindrome (24242).

The spelling of 20140 in words is "twenty thousand, one hundred forty", and thus it is an iban number.