4020 has 24 divisors (see below), whose sum is σ = 11424. Its totient is φ = 1056.

The previous prime is 4019. The next prime is 4021. The reversal of 4020 is 204.

4020 is an esthetic number in base 9, because in such base its adjacent digits differ by 1.

It is an interprime number because it is at equal distance from previous prime (4019) and next prime (4021).

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a nialpdrome in base 8 and base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4021) 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, 27 + ... + 93.

It is an arithmetic number, because the mean of its divisors is an integer number (476).

2⁴⁰²⁰ 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 4020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5712).

4020 is an abundant number, since it is smaller than the sum of its proper divisors (7404).

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

4020 is a wasteful number, since it uses less digits than its factorization.

4020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 6.

The square root of 4020 is about 63.4034699366. The cubic root of 4020 is about 15.9004232315.

Adding to 4020 its reverse (204), we get a palindrome (4224).

The spelling of 4020 in words is "four thousand, twenty", and thus it is an iban number.