28231616 has 112 divisors (see below), whose sum is σ = 69128640. Its totient is φ = 11182080.

The previous prime is 28231613. The next prime is 28231627. The reversal of 28231616 is 61613282.

It is a tau number, because it is divible by the number of its divisors (112).

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28231613) 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 15 ways as a sum of consecutive naturals, for example, 532646 + ... + 532698.

It is an arithmetic number, because the mean of its divisors is an integer number (617220).

Almost surely, 2^28231616 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 28231616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34564320).

28231616 is an abundant number, since it is smaller than the sum of its proper divisors (40897024).

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

28231616 is a wasteful number, since it uses less digits than its factorization.

28231616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142 (or 132 counting only the distinct ones).

The product of its digits is 3456, while the sum is 29.

The square root of 28231616 is about 5313.3432036713. The cubic root of 28231616 is about 304.4938878540.

Adding to 28231616 its reverse (61613282), we get a palindrome (89844898).

The spelling of 28231616 in words is "twenty-eight million, two hundred thirty-one thousand, six hundred sixteen".