28271018021 has 2 divisors, whose sum is σ = 28271018022. Its totient is φ = 28271018020.

The previous prime is 28271017967. The next prime is 28271018029. The reversal of 28271018021 is 12081017282.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19394740225 + 8876277796 = 139265^2 + 94214^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28271018021 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28271018029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14135509010 + 14135509011.

It is an arithmetic number, because the mean of its divisors is an integer number (14135509011).

Almost surely, 2^28271018021 is an apocalyptic number.

It is an amenable number.

28271018021 is a deficient number, since it is larger than the sum of its proper divisors (1).

28271018021 is an equidigital number, since it uses as much as digits as its factorization.

28271018021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3584, while the sum is 32.

The spelling of 28271018021 in words is "twenty-eight billion, two hundred seventy-one million, eighteen thousand, twenty-one".