| Base | Representation |
|---|---|
| bin | 1001010001110111111100… |
| … | …00101000010110000100000 |
| 3 | 2200020201210102220112100000 |
| 4 | 10220323332011002300200 |
| 5 | 10133310132443002010 |
| 6 | 111222031453500000 |
| 7 | 4204144531006200 |
| oct | 450737605026040 |
| 9 | 80221712815300 |
| 10 | 20405357390880 |
| 11 | 655795530a500 |
| 12 | 2356840aa1600 |
| 13 | b502a8823c47 |
| 14 | 5078a5b54400 |
| 15 | 255bcbc7e7c0 |
| hex | 128efe142c20 |
20405357390880 has 5184 divisors, whose sum is σ = 100937244635136. Its totient is φ = 3862668902400.
The previous prime is 20405357390851. The next prime is 20405357390881. The reversal of 20405357390880 is 8809375350402.
20405357390880 is a `hidden beast` number, since 2 + 0 + 405 + 3 + 5 + 73 + 90 + 8 + 80 = 666.
It is a super-2 number, since 2×204053573908802 (a number of 27 digits) contains 22 as substring.
It is a Harshad number since it is a multiple of its sum of digits (54).
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (20405357390881) by changing a digit.
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 863 ways as a sum of consecutive naturals, for example, 160672105377 + ... + 160672105503.
It is an arithmetic number, because the mean of its divisors is an integer number (19470919104).
Almost surely, 220405357390880 is an apocalyptic number.
20405357390880 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 20405357390880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50468622317568).
20405357390880 is an abundant number, since it is smaller than the sum of its proper divisors (80531887244256).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
20405357390880 is a wasteful number, since it uses less digits than its factorization.
20405357390880 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 251 (or 213 counting only the distinct ones).
The product of its (nonzero) digits is 7257600, while the sum is 54.
The spelling of 20405357390880 in words is "twenty trillion, four hundred five billion, three hundred fifty-seven million, three hundred ninety thousand, eight hundred eighty".
• e-mail: info -at- numbersaplenty.com • Privacy notice • done in 0.111 sec. • engine limits •