28018047809 has 2 divisors, whose sum is σ = 28018047810. Its totient is φ = 28018047808.

The previous prime is 28018047797. The next prime is 28018047817. The reversal of 28018047809 is 90874081082.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27137620225 + 880427584 = 164735^2 + 29672^2 .

It is a cyclic number.

It is not a de Polignac number, because 28018047809 - 2⁸ = 28018047553 is a prime.

It is a super-2 number, since 2×28018047809² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28018047859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14009023904 + 14009023905.

It is an arithmetic number, because the mean of its divisors is an integer number (14009023905).

Almost surely, 2^28018047809 is an apocalyptic number.

It is an amenable number.

28018047809 is a deficient number, since it is larger than the sum of its proper divisors (1).

28018047809 is an equidigital number, since it uses as much as digits as its factorization.

28018047809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 258048, while the sum is 47.

The spelling of 28018047809 in words is "twenty-eight billion, eighteen million, forty-seven thousand, eight hundred nine".