20405343416320 has 208 divisors, whose sum is σ = 49606739425152. Its totient is φ = 8055674961920.

The previous prime is 20405343416303. The next prime is 20405343416329. The reversal of 20405343416320 is 2361434350402.

It is a self number, because there is not a number n which added to its sum of digits gives 20405343416320.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20405343416329) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1854519939 + ... + 1854530941.

It is an arithmetic number, because the mean of its divisors is an integer number (238493939544).

Almost surely, 2^{20405343416320} is an apocalyptic number.

20405343416320 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 20405343416320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24803369712576).

20405343416320 is an abundant number, since it is smaller than the sum of its proper divisors (29201396008832).

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

20405343416320 is a wasteful number, since it uses less digits than its factorization.

20405343416320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12206 (or 12184 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 37.

Adding to 20405343416320 its reverse (2361434350402), we get a palindrome (22766777766722).

The spelling of 20405343416320 in words is "twenty trillion, four hundred five billion, three hundred forty-three million, four hundred sixteen thousand, three hundred twenty".