28431216 has 160 divisors (see below), whose sum is σ = 92375040. Its totient is φ = 8294400.

The previous prime is 28431211. The next prime is 28431217. The reversal of 28431216 is 61213482.

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

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

It is a self number, because there is not a number n which added to its sum of digits gives 28431216.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28431211) 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 31 ways as a sum of consecutive naturals, for example, 147216 + ... + 147408.

It is an arithmetic number, because the mean of its divisors is an integer number (577344).

Almost surely, 2^28431216 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 28431216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46187520).

28431216 is an abundant number, since it is smaller than the sum of its proper divisors (63943824).

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

28431216 is a wasteful number, since it uses less digits than its factorization.

28431216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252 (or 240 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 28431216 is about 5332.0930224444. The cubic root of 28431216 is about 305.2098027950.

Adding to 28431216 its reverse (61213482), we get a palindrome (89644698).

The spelling of 28431216 in words is "twenty-eight million, four hundred thirty-one thousand, two hundred sixteen".