20440400540 has 96 divisors (see below), whose sum is σ = 49388258304. Its totient is φ = 6960983040.

The previous prime is 20440400527. The next prime is 20440400543. The reversal of 20440400540 is 4500404402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20440400543) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23043977 + ... + 23044863.

It is an arithmetic number, because the mean of its divisors is an integer number (514461024).

Almost surely, 2^20440400540 is an apocalyptic number.

20440400540 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 20440400540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24694129152).

20440400540 is an abundant number, since it is smaller than the sum of its proper divisors (28947857764).

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

20440400540 is a wasteful number, since it uses less digits than its factorization.

20440400540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1827 (or 1825 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 23.

Adding to 20440400540 its reverse (4500404402), we get a palindrome (24940804942).

The spelling of 20440400540 in words is "twenty billion, four hundred forty million, four hundred thousand, five hundred forty".