40420 has 24 divisors (see below), whose sum is σ = 88704. Its totient is φ = 15456.

The previous prime is 40387. The next prime is 40423. The reversal of 40420 is 2404.

40420 = 3² + 4² + ... + 49².

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

It is a junction number, because it is equal to n+sod(n) for n = 40397 and 40406.

It is not an unprimeable number, because it can be changed into a prime (40423) by changing a digit.

40420 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 7 ways as a sum of consecutive naturals, for example, 837 + ... + 883.

It is an arithmetic number, because the mean of its divisors is an integer number (3696).

2⁴⁰⁴²⁰ 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 40420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44352).

40420 is an abundant number, since it is smaller than the sum of its proper divisors (48284).

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

40420 is a wasteful number, since it uses less digits than its factorization.

40420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99 (or 97 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 10.

The square root of 40420 is about 201.0472581260. The cubic root of 40420 is about 34.3188007326.

Adding to 40420 its reverse (2404), we get a palindrome (42824).

It can be divided in two parts, 404 and 20, that added together give a palindrome (424).

The spelling of 40420 in words is "forty thousand, four hundred twenty", and thus it is an iban number.