40820 has 24 divisors (see below), whose sum is σ = 92904. Its totient is φ = 14976.

The previous prime is 40819. The next prime is 40823. The reversal of 40820 is 2804.

It can be written as a sum of positive squares in 4 ways, for example, as 16 + 40804 = 4^2 + 202^2 .

It is a junction number, because it is equal to n+sod(n) for n = 40795 and 40804.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 40820.

It is not an unprimeable number, because it can be changed into a prime (40823) 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, 182 + ... + 338.

It is an arithmetic number, because the mean of its divisors is an integer number (3871).

2⁴⁰⁸²⁰ 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 40820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46452).

40820 is an abundant number, since it is smaller than the sum of its proper divisors (52084).

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

40820 is a wasteful number, since it uses less digits than its factorization.

40820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 40820 is about 202.0396000788. The cubic root of 40820 is about 34.4316366611.

The spelling of 40820 in words is "forty thousand, eight hundred twenty".