27728 has 10 divisors (see below), whose sum is σ = 53754. Its totient is φ = 13856.

The previous prime is 27701. The next prime is 27733. The reversal of 27728 is 82772.

27728 is nontrivially palindromic in base 15.

It can be written as a sum of positive squares in only one way, i.e., 23104 + 4624 = 152^2 + 68^2 .

It is a junction number, because it is equal to n+sod(n) for n = 27697 and 27706.

It is a congruent number.

It is an unprimeable number.

27728 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 851 + ... + 882.

2²⁷⁷²⁸ is an apocalyptic number.

It is an amenable number.

27728 is a deficient number, since it is larger than the sum of its proper divisors (26026).

27728 is a wasteful number, since it uses less digits than its factorization.

27728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1741 (or 1735 counting only the distinct ones).

The product of its digits is 1568, while the sum is 26.

The square root of 27728 is about 166.5172663720. The cubic root of 27728 is about 30.2672419521.

The spelling of 27728 in words is "twenty-seven thousand, seven hundred twenty-eight".