28217107 has 4 divisors (see below), whose sum is σ = 28267096. Its totient is φ = 28167120.

The previous prime is 28217089. The next prime is 28217131. The reversal of 28217107 is 70171282.

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 28217107 - 2¹¹ = 28215059 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28217407) 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, 24138 + ... + 25279.

It is an arithmetic number, because the mean of its divisors is an integer number (7066774).

Almost surely, 2^28217107 is an apocalyptic number.

28217107 is a deficient number, since it is larger than the sum of its proper divisors (49989).

28217107 is an equidigital number, since it uses as much as digits as its factorization.

28217107 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49988.

The product of its (nonzero) digits is 1568, while the sum is 28.

The square root of 28217107 is about 5311.9776919712. The cubic root of 28217107 is about 304.4417163351.

Adding to 28217107 its reverse (70171282), we get a palindrome (98388389).

The spelling of 28217107 in words is "twenty-eight million, two hundred seventeen thousand, one hundred seven".