Search a number
-
+
8921 = 11811
BaseRepresentation
bin10001011011001
3110020102
42023121
5241141
6105145
735003
oct21331
913212
108921
116780
1251b5
1340a3
143373
15299b
hex22d9

8921 has 4 divisors (see below), whose sum is σ = 9744. Its totient is φ = 8100.

The previous prime is 8893. The next prime is 8923. The reversal of 8921 is 1298.

8921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2k-8921 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a plaindrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 8893 and 8902.

It is not an unprimeable number, because it can be changed into a prime (8923) 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, 395 + ... + 416.

It is an arithmetic number, because the mean of its divisors is an integer number (2436).

28921 is an apocalyptic number.

It is an amenable number.

8921 is a deficient number, since it is larger than the sum of its proper divisors (823).

8921 is a wasteful number, since it uses less digits than its factorization.

8921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 822.

The product of its digits is 144, while the sum is 20.

The square root of 8921 is about 94.4510455209. The cubic root of 8921 is about 20.7397975683.

It can be divided in two parts, 8 and 921, that added together give a palindrome (929).

The spelling of 8921 in words is "eight thousand, nine hundred twenty-one".

Divisors: 1 11 811 8921