28091232 has 192 divisors, whose sum is σ = 91869120. Its totient is φ = 8294400.

The previous prime is 28091213. The next prime is 28091249. The reversal of 28091232 is 23219082.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 28091196 and 28091205.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 460482 + ... + 460542.

It is an arithmetic number, because the mean of its divisors is an integer number (478485).

Almost surely, 2^28091232 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28091232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45934560).

28091232 is an abundant number, since it is smaller than the sum of its proper divisors (63777888).

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

28091232 is a wasteful number, since it uses less digits than its factorization.

28091232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134 (or 120 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 28091232 is about 5300.1162251407. The cubic root of 28091232 is about 303.9883421199.

The spelling of 28091232 in words is "twenty-eight million, ninety-one thousand, two hundred thirty-two".