28712 has 16 divisors (see below), whose sum is σ = 55860. Its totient is φ = 13824.

The previous prime is 28711. The next prime is 28723. The reversal of 28712 is 21782.

It can be written as a sum of positive squares in 2 ways, for example, as 27556 + 1156 = 166^2 + 34^2 .

It is not an unprimeable number, because it can be changed into a prime (28711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 248 + ... + 344.

2²⁸⁷¹² is an apocalyptic number.

It is an amenable number.

28712 is a deficient number, since it is larger than the sum of its proper divisors (27148).

28712 is a wasteful number, since it uses less digits than its factorization.

28712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140 (or 136 counting only the distinct ones).

The product of its digits is 224, while the sum is 20.

The square root of 28712 is about 169.4461566398. The cubic root of 28712 is about 30.6211254296.

It can be divided in two parts, 2 and 8712, that multiplied together give a square (17424 = 132²).

The spelling of 28712 in words is "twenty-eight thousand, seven hundred twelve".