20439840860 has 96 divisors (see below), whose sum is σ = 46388764800. Its totient is φ = 7537287168.

The previous prime is 20439840853. The next prime is 20439840907. The reversal of 20439840860 is 6804893402.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3695417 + ... + 3700943.

It is an arithmetic number, because the mean of its divisors is an integer number (483216300).

Almost surely, 2^20439840860 is an apocalyptic number.

20439840860 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 20439840860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23194382400).

20439840860 is an abundant number, since it is smaller than the sum of its proper divisors (25948923940).

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

20439840860 is a wasteful number, since it uses less digits than its factorization.

20439840860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5775 (or 5773 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 44.

The spelling of 20439840860 in words is "twenty billion, four hundred thirty-nine million, eight hundred forty thousand, eight hundred sixty".