28281332 has 6 divisors (see below), whose sum is σ = 49492338. Its totient is φ = 14140664.

The previous prime is 28281311. The next prime is 28281343. The reversal of 28281332 is 23318282.

It can be written as a sum of positive squares in only one way, i.e., 17757796 + 10523536 = 4214^2 + 3244^2 .

It is a junction number, because it is equal to n+sod(n) for n = 28281295 and 28281304.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3535163 + ... + 3535170.

It is an arithmetic number, because the mean of its divisors is an integer number (8248723).

Almost surely, 2^28281332 is an apocalyptic number.

It is an amenable number.

28281332 is a deficient number, since it is larger than the sum of its proper divisors (21211006).

28281332 is a wasteful number, since it uses less digits than its factorization.

28281332 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7070337 (or 7070335 counting only the distinct ones).

The product of its digits is 4608, while the sum is 29.

The square root of 28281332 is about 5318.0195561882. The cubic root of 28281332 is about 304.6725213956.

The spelling of 28281332 in words is "twenty-eight million, two hundred eighty-one thousand, three hundred thirty-two".