| Base | Representation |
|---|---|
| bin | 100101111110000010… |
| … | …1110101111011000000 |
| 3 | 21210110120122021121100 |
| 4 | 1023330011311323000 |
| 5 | 2313442413120334 |
| 6 | 101243003254400 |
| 7 | 5614415242620 |
| oct | 1137405657300 |
| 9 | 253416567540 |
| 10 | 81538801344 |
| 11 | 31642589330 |
| 12 | 1397721a400 |
| 13 | 78c5b91160 |
| 14 | 3d3729c880 |
| 15 | 21c362ec99 |
| hex | 12fc175ec0 |
81538801344 has 672 divisors, whose sum is σ = 317078221824. Its totient is φ = 19345858560.
The previous prime is 81538801307. The next prime is 81538801349. The reversal of 81538801344 is 44310883518.
81538801344 is a `hidden beast` number, since 8 + 1 + 538 + 80 + 1 + 34 + 4 = 666.
It is a tau number, because it is divible by the number of its divisors (672).
It is a super-2 number, since 2×815388013442 (a number of 23 digits) contains 22 as substring.
It is a self number, because there is not a number n which added to its sum of digits gives 81538801344.
It is not an unprimeable number, because it can be changed into a prime (81538801349) 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 95 ways as a sum of consecutive naturals, for example, 59386642 + ... + 59388014.
It is an arithmetic number, because the mean of its divisors is an integer number (471842592).
Almost surely, 281538801344 is an apocalyptic number.
81538801344 is a gapful number since it is divisible by the number (84) 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 81538801344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (158539110912).
81538801344 is an abundant number, since it is smaller than the sum of its proper divisors (235539420480).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
81538801344 is a wasteful number, since it uses less digits than its factorization.
81538801344 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 1525 (or 1512 counting only the distinct ones).
The product of its (nonzero) digits is 368640, while the sum is 45.
The spelling of 81538801344 in words is "eighty-one billion, five hundred thirty-eight million, eight hundred one thousand, three hundred forty-four".
• e-mail: info -at- numbersaplenty.com • Privacy notice • done in 0.067 sec. • engine limits •