20400440120 has 64 divisors (see below), whose sum is σ = 47054113920. Its totient is φ = 7955869824.

The previous prime is 20400440119. The next prime is 20400440131. The reversal of 20400440120 is 2104400402.

It is a super-2 number, since 2×20400440120² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 957827 + ... + 978893.

It is an arithmetic number, because the mean of its divisors is an integer number (735220530).

Almost surely, 2^20400440120 is an apocalyptic number.

20400440120 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 20400440120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23527056960).

20400440120 is an abundant number, since it is smaller than the sum of its proper divisors (26653673800).

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

20400440120 is a wasteful number, since it uses less digits than its factorization.

20400440120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21684 (or 21680 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 17.

Adding to 20400440120 its reverse (2104400402), we get a palindrome (22504840522).

The spelling of 20400440120 in words is "twenty billion, four hundred million, four hundred forty thousand, one hundred twenty".