Search a number
BaseRepresentation
bin111000000111001
31110102001
413000321
51404404
6341001
7146521
oct70071
943361
1028729
111a648
1214761
13100cc
14a681
1587a4
hex7039

28729 has 2 divisors, whose sum is σ = 28730. Its totient is φ = 28728.

The previous prime is 28723. The next prime is 28751. The reversal of 28729 is 92782.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23104 + 5625 = 152^2 + 75^2 .

It is a cyclic number.

It is not a de Polignac number, because 28729 - 25 = 28697 is a prime.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 28697 and 28706.

It is not a weakly prime, because it can be changed into another prime (28723) 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 as a sum of consecutive naturals, namely, 14364 + 14365.

It is an arithmetic number, because the mean of its divisors is an integer number (14365).

228729 is an apocalyptic number.

It is an amenable number.

28729 is a deficient number, since it is larger than the sum of its proper divisors (1).

28729 is an equidigital number, since it uses as much as digits as its factorization.

28729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2016, while the sum is 28.

The square root of 28729 is about 169.4963126443. The cubic root of 28729 is about 30.6271676933.

It can be divided in two parts, 28 and 729, that added together give a palindrome (757).

The spelling of 28729 in words is "twenty-eight thousand, seven hundred twenty-nine".