28236491771 has 4 divisors (see below), whose sum is σ = 28244289072. Its totient is φ = 28228694472.

The previous prime is 28236491743. The next prime is 28236491779. The reversal of 28236491771 is 17719463282.

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 28236491771 - 2³⁰ = 27162749947 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28236491779) 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, 3893216 + ... + 3900461.

It is an arithmetic number, because the mean of its divisors is an integer number (7061072268).

Almost surely, 2^28236491771 is an apocalyptic number.

28236491771 is a deficient number, since it is larger than the sum of its proper divisors (7797301).

28236491771 is an equidigital number, since it uses as much as digits as its factorization.

28236491771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7797300.

The product of its digits is 1016064, while the sum is 50.

The spelling of 28236491771 in words is "twenty-eight billion, two hundred thirty-six million, four hundred ninety-one thousand, seven hundred seventy-one".