| Base | Representation |
|---|---|
| bin | 101000000011… |
| … | …1001111110000 |
| 3 | 1110111222020020 |
| 4 | 1100013033300 |
| 5 | 20334014300 |
| 6 | 2030043440 |
| 7 | 343335663 |
| oct | 120071760 |
| 9 | 43458206 |
| 10 | 21001200 |
| 11 | 10944570 |
| 12 | 7049580 |
| 13 | 447405c |
| 14 | 2b096da |
| 15 | 1c9c8a0 |
| hex | 14073f0 |
21001200 has 240 divisors, whose sum is σ = 77126016. Its totient is φ = 4838400.
The previous prime is 21001187. The next prime is 21001247. The reversal of 21001200 is 210012.
It is a happy number.
It is a tau number, because it is divible by the number of its divisors (240).
It is a Harshad number since it is a multiple of its sum of digits (6).
It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.
It is a congruent number.
It is an unprimeable number.
It is a pernicious number, because its binary representation contains a prime number (11) of ones.
It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 488379 + ... + 488421.
Almost surely, 221001200 is an apocalyptic number.
21001200 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 21001200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38563008).
21001200 is an abundant number, since it is smaller than the sum of its proper divisors (56124816).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
21001200 is a wasteful number, since it uses less digits than its factorization.
21001200 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 112 (or 101 counting only the distinct ones).
The product of its (nonzero) digits is 4, while the sum is 6.
The square root of 21001200 is about 4582.7066238196. The cubic root of 21001200 is about 275.8976726317.
Adding to 21001200 its reverse (210012), we get a palindrome (21211212).
Multiplying 21001200 by its reverse (210012), we get a square (4410504014400 = 21001202).
21001200 divided by its reverse (210012) gives a square (100 = 102).
The spelling of 21001200 in words is "twenty-one million, one thousand, two hundred".
• e-mail: info -at- numbersaplenty.com • Privacy notice • done in 0.066 sec. • engine limits •