28388107 has 4 divisors (see below), whose sum is σ = 30968856. Its totient is φ = 25807360.

The previous prime is 28388099. The next prime is 28388111. The reversal of 28388107 is 70188382.

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 28388107 - 2³ = 28388099 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28388137) 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, 1290358 + ... + 1290379.

It is an arithmetic number, because the mean of its divisors is an integer number (7742214).

Almost surely, 2^28388107 is an apocalyptic number.

28388107 is a deficient number, since it is larger than the sum of its proper divisors (2580749).

28388107 is a wasteful number, since it uses less digits than its factorization.

28388107 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2580748.

The product of its (nonzero) digits is 21504, while the sum is 37.

The square root of 28388107 is about 5328.0490801043. The cubic root of 28388107 is about 305.0554660391.

The spelling of 28388107 in words is "twenty-eight million, three hundred eighty-eight thousand, one hundred seven".