28289232 has 30 divisors (see below), whose sum is σ = 79170962. Its totient is φ = 9429696.

The previous prime is 28289231. The next prime is 28289237. The reversal of 28289232 is 23298282.

It can be written as a sum of positive squares in only one way, i.e., 28132416 + 156816 = 5304^2 + 396^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28289231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 98083 + ... + 98370.

Almost surely, 2^28289232 is an apocalyptic number.

It is an amenable number.

28289232 is an abundant number, since it is smaller than the sum of its proper divisors (50881730).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28289232 is a wasteful number, since it uses less digits than its factorization.

28289232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196467 (or 196458 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 28289232 is about 5318.7622620305. The cubic root of 28289232 is about 304.7008874433.

The spelling of 28289232 in words is "twenty-eight million, two hundred eighty-nine thousand, two hundred thirty-two".