Base | Representation |
---|---|
bin | 101000001111… |
… | …1011000001000 |
3 | 1110200222210222 |
4 | 1100133120020 |
5 | 20400200130 |
6 | 2032125212 |
7 | 344230103 |
oct | 120373010 |
9 | 43628728 |
10 | 21100040 |
11 | 10a01855 |
12 | 7096808 |
13 | 44aa040 |
14 | 2b3373a |
15 | 1cbbce5 |
hex | 141f608 |
21100040 has 32 divisors (see below), whose sum is σ = 51128280. Its totient is φ = 7790592.
The previous prime is 21100033. The next prime is 21100049. The reversal of 21100040 is 4000112.
It can be written as a sum of positive squares in 4 ways, for example, as 14577124 + 6522916 = 3818^2 + 2554^2 .
It is a Harshad number since it is a multiple of its sum of digits (8).
It is not an unprimeable number, because it can be changed into a prime (21100049) by changing a digit.
It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19769 + ... + 20808.
Almost surely, 221100040 is an apocalyptic number.
21100040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.
It is an amenable number.
21100040 is an abundant number, since it is smaller than the sum of its proper divisors (30028240).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
21100040 is a wasteful number, since it uses less digits than its factorization.
21100040 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 40601 (or 40597 counting only the distinct ones).
The product of its (nonzero) digits is 8, while the sum is 8.
The square root of 21100040 is about 4593.4779851437. The cubic root of 21100040 is about 276.3298234412.
Adding to 21100040 its reverse (4000112), we get a palindrome (25100152).
The spelling of 21100040 in words is "twenty-one million, one hundred thousand, forty".
• e-mail: info -at- numbersaplenty.com • Privacy notice • done in 0.065 sec. • engine limits •