28042216 has 8 divisors (see below), whose sum is σ = 52579170. Its totient is φ = 14021104.

The previous prime is 28042211. The next prime is 28042219. The reversal of 28042216 is 61224082.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 26728900 + 1313316 = 5170^2 + 1146^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (28042211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1752631 + ... + 1752646.

Almost surely, 2^28042216 is an apocalyptic number.

It is an amenable number.

28042216 is a deficient number, since it is larger than the sum of its proper divisors (24536954).

28042216 is a wasteful number, since it uses less digits than its factorization.

28042216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3505283 (or 3505279 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 25.

The square root of 28042216 is about 5295.4901567277. The cubic root of 28042216 is about 303.8114308399.

Adding to 28042216 its reverse (61224082), we get a palindrome (89266298).

The spelling of 28042216 in words is "twenty-eight million, forty-two thousand, two hundred sixteen".