28788817 has 4 divisors (see below), whose sum is σ = 28823040. Its totient is φ = 28754596.

The previous prime is 28788787. The next prime is 28788827. The reversal of 28788817 is 71888782.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28788817 - 2⁷ = 28788689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28788827) 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, 15817 + ... + 17542.

It is an arithmetic number, because the mean of its divisors is an integer number (7205760).

Almost surely, 2^28788817 is an apocalyptic number.

It is an amenable number.

28788817 is a deficient number, since it is larger than the sum of its proper divisors (34223).

28788817 is an equidigital number, since it uses as much as digits as its factorization.

28788817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34222.

The product of its digits is 401408, while the sum is 49.

The square root of 28788817 is about 5365.5211303283. The cubic root of 28788817 is about 306.4840935694.

The spelling of 28788817 in words is "twenty-eight million, seven hundred eighty-eight thousand, eight hundred seventeen".