20424040 has 128 divisors (see below), whose sum is σ = 58705920. Its totient is φ = 6220800.

The previous prime is 20423989. The next prime is 20424043. The reversal of 20424040 is 4042402.

It is not an unprimeable number, because it can be changed into a prime (20424043) 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 31 ways as a sum of consecutive naturals, for example, 112750 + ... + 112930.

It is an arithmetic number, because the mean of its divisors is an integer number (458640).

Almost surely, 2^20424040 is an apocalyptic number.

20424040 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 20424040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29352960).

20424040 is an abundant number, since it is smaller than the sum of its proper divisors (38281880).

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

20424040 is a wasteful number, since it uses less digits than its factorization.

20424040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243 (or 239 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 16.

The square root of 20424040 is about 4519.2964054153. The cubic root of 20424040 is about 273.3467307862.

Adding to 20424040 its reverse (4042402), we get a palindrome (24466442).

The spelling of 20424040 in words is "twenty million, four hundred twenty-four thousand, forty".