28307216 has 60 divisors (see below), whose sum is σ = 65013696. Its totient is φ = 11695680.

The previous prime is 28307189. The next prime is 28307231. The reversal of 28307216 is 61270382.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 107501 + ... + 107763.

Almost surely, 2^28307216 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 28307216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32506848).

28307216 is an abundant number, since it is smaller than the sum of its proper divisors (36706480).

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

28307216 is a wasteful number, since it uses less digits than its factorization.

28307216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 340 (or 303 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 28307216 is about 5320.4526123254. The cubic root of 28307216 is about 304.7654418054.

Adding to 28307216 its reverse (61270382), we get a palindrome (89577598).

The spelling of 28307216 in words is "twenty-eight million, three hundred seven thousand, two hundred sixteen".