Search a number
-
+
22805 = 54561
BaseRepresentation
bin101100100010101
31011021122
411210111
51212210
6253325
7123326
oct54425
934248
1022805
1116152
1211245
13a4c3
14844d
156b55
hex5915

22805 has 4 divisors (see below), whose sum is σ = 27372. Its totient is φ = 18240.

The previous prime is 22787. The next prime is 22807. The reversal of 22805 is 50822.

22805 = T93 + T94 + ... + T97.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50822 = 225411.

It can be written as a sum of positive squares in 2 ways, for example, as 7921 + 14884 = 89^2 + 122^2 .

It is not a de Polignac number, because 22805 - 26 = 22741 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2276 + ... + 2285.

It is an arithmetic number, because the mean of its divisors is an integer number (6843).

222805 is an apocalyptic number.

It is an amenable number.

22805 is a deficient number, since it is larger than the sum of its proper divisors (4567).

22805 is an equidigital number, since it uses as much as digits as its factorization.

22805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4566.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 22805 is about 151.0132444523. The cubic root of 22805 is about 28.3580714358.

Adding to 22805 its sum of digits (17), we get a palindrome (22822).

The spelling of 22805 in words is "twenty-two thousand, eight hundred five".

Divisors: 1 5 4561 22805