28211886791 has 4 divisors (see below), whose sum is σ = 30776603784. Its totient is φ = 25647169800.

The previous prime is 28211886743. The next prime is 28211886827. The reversal of 28211886791 is 19768811282.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28211886791 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28211886491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1282358480 + ... + 1282358501.

It is an arithmetic number, because the mean of its divisors is an integer number (7694150946).

Almost surely, 2^28211886791 is an apocalyptic number.

28211886791 is a deficient number, since it is larger than the sum of its proper divisors (2564716993).

28211886791 is a wasteful number, since it uses less digits than its factorization.

28211886791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2564716992.

The product of its digits is 774144, while the sum is 53.

The spelling of 28211886791 in words is "twenty-eight billion, two hundred eleven million, eight hundred eighty-six thousand, seven hundred ninety-one".