20040440 has 64 divisors (see below), whose sum is σ = 54259200. Its totient is φ = 6507648.

The previous prime is 20040409. The next prime is 20040443. The reversal of 20040440 is 4404002.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20040443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3437 + ... + 7203.

It is an arithmetic number, because the mean of its divisors is an integer number (847800).

Almost surely, 2^20040440 is an apocalyptic number.

20040440 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 20040440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27129600).

20040440 is an abundant number, since it is smaller than the sum of its proper divisors (34218760).

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

20040440 is a wasteful number, since it uses less digits than its factorization.

20040440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3804 (or 3800 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 14.

The square root of 20040440 is about 4476.6550012258. The cubic root of 20040440 is about 271.6245902357.

Adding to 20040440 its reverse (4404002), we get a palindrome (24444442).

The spelling of 20040440 in words is "twenty million, forty thousand, four hundred forty".