28041215 has 4 divisors (see below), whose sum is σ = 33649464. Its totient is φ = 22432968.

The previous prime is 28041199. The next prime is 28041217. The reversal of 28041215 is 51214082.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28041215 - 2⁴ = 28041199 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28041217) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2804117 + ... + 2804126.

It is an arithmetic number, because the mean of its divisors is an integer number (8412366).

Almost surely, 2^28041215 is an apocalyptic number.

28041215 is a deficient number, since it is larger than the sum of its proper divisors (5608249).

28041215 is an equidigital number, since it uses as much as digits as its factorization.

28041215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5608248.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 28041215 is about 5295.3956414984. The cubic root of 28041215 is about 303.8078158277.

Adding to 28041215 its reverse (51214082), we get a palindrome (79255297).

The spelling of 28041215 in words is "twenty-eight million, forty-one thousand, two hundred fifteen".