20021331400 has 288 divisors, whose sum is σ = 56894572800. Its totient is φ = 6524582400.

The previous prime is 20021331391. The next prime is 20021331401. The reversal of 20021331400 is 413312002.

It is a happy number.

It is a super-2 number, since 2×20021331400² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021331401) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 17923642 + ... + 17924758.

It is an arithmetic number, because the mean of its divisors is an integer number (197550600).

Almost surely, 2^20021331400 is an apocalyptic number.

20021331400 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 20021331400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28447286400).

20021331400 is an abundant number, since it is smaller than the sum of its proper divisors (36873241400).

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

20021331400 is a wasteful number, since it uses less digits than its factorization.

20021331400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1237 (or 1221 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

Adding to 20021331400 its reverse (413312002), we get a palindrome (20434643402).

The spelling of 20021331400 in words is "twenty billion, twenty-one million, three hundred thirty-one thousand, four hundred".