28851766561 has 2 divisors, whose sum is σ = 28851766562. Its totient is φ = 28851766560.

The previous prime is 28851766499. The next prime is 28851766579. The reversal of 28851766561 is 16566715882.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27830580625 + 1021185936 = 166825^2 + 31956^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28851766561 is a prime.

It is not a weakly prime, because it can be changed into another prime (28851766961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14425883280 + 14425883281.

It is an arithmetic number, because the mean of its divisors is an integer number (14425883281).

Almost surely, 2^28851766561 is an apocalyptic number.

It is an amenable number.

28851766561 is a deficient number, since it is larger than the sum of its proper divisors (1).

28851766561 is an equidigital number, since it uses as much as digits as its factorization.

28851766561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4838400, while the sum is 55.

The spelling of 28851766561 in words is "twenty-eight billion, eight hundred fifty-one million, seven hundred sixty-six thousand, five hundred sixty-one".