20023840 has 24 divisors (see below), whose sum is σ = 47306700. Its totient is φ = 8009472.

The previous prime is 20023837. The next prime is 20023847. The reversal of 20023840 is 4832002.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 19678096 + 345744 = 4436^2 + 588^2 .

It is not an unprimeable number, because it can be changed into a prime (20023847) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 62415 + ... + 62734.

Almost surely, 2^20023840 is an apocalyptic number.

20023840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20023840 is an abundant number, since it is smaller than the sum of its proper divisors (27282860).

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

20023840 is a wasteful number, since it uses less digits than its factorization.

20023840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125164 (or 125156 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 20023840 is about 4474.8005542147. The cubic root of 20023840 is about 271.5495716943.

Adding to 20023840 its reverse (4832002), we get a palindrome (24855842).

The spelling of 20023840 in words is "twenty million, twenty-three thousand, eight hundred forty".