20402040400 has 240 divisors, whose sum is σ = 59566008960. Its totient is φ = 6559488000.

The previous prime is 20402040383. The next prime is 20402040403. The reversal of 20402040400 is 404020402.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20402040403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5371302 + ... + 5375098.

It is an arithmetic number, because the mean of its divisors is an integer number (248191704).

Almost surely, 2^20402040400 is an apocalyptic number.

20402040400 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 20402040400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29783004480).

20402040400 is an abundant number, since it is smaller than the sum of its proper divisors (39163968560).

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

20402040400 is a wasteful number, since it uses less digits than its factorization.

20402040400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3942 (or 3931 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 16.

Adding to 20402040400 its reverse (404020402), we get a palindrome (20806060802).

It can be divided in two parts, 204020 and 40400, that multiplied together give a cube (8242408000 = 2020³).

The spelling of 20402040400 in words is "twenty billion, four hundred two million, forty thousand, four hundred".