20423440000 has 160 divisors (see below), whose sum is σ = 51716570400. Its totient is φ = 8029056000.

The previous prime is 20423439989. The next prime is 20423440027. The reversal of 20423440000 is 4432402.

It is a tau number, because it is divible by the number of its divisors (160).

It is a self number, because there is not a number n which added to its sum of digits gives 20423440000.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 4717837 + ... + 4722163.

It is an arithmetic number, because the mean of its divisors is an integer number (323228565).

Almost surely, 2^20423440000 is an apocalyptic number.

20423440000 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 20423440000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25858285200).

20423440000 is an abundant number, since it is smaller than the sum of its proper divisors (31293130400).

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

20423440000 is an frugal number, since it uses more digits than its factorization.

20423440000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4420 (or 4393 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 19.

Adding to 20423440000 its reverse (4432402), we get a palindrome (20427872402).

The spelling of 20423440000 in words is "twenty billion, four hundred twenty-three million, four hundred forty thousand".