20440340440 has 96 divisors (see below), whose sum is σ = 49863649680. Its totient is φ = 7537660416.

The previous prime is 20440340413. The next prime is 20440340447. The reversal of 20440340440 is 4404304402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20440340447) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7549567 + ... + 7552273.

Almost surely, 2^20440340440 is an apocalyptic number.

20440340440 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 20440340440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24931824840).

20440340440 is an abundant number, since it is smaller than the sum of its proper divisors (29423309240).

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

20440340440 is a wasteful number, since it uses less digits than its factorization.

20440340440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3861 (or 3844 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 25.

Adding to 20440340440 its reverse (4404304402), we get a palindrome (24844644842).

The spelling of 20440340440 in words is "twenty billion, four hundred forty million, three hundred forty thousand, four hundred forty".