28817873441561 has 2 divisors, whose sum is σ = 28817873441562. Its totient is φ = 28817873441560.

The previous prime is 28817873441503. The next prime is 28817873441629. The reversal of 28817873441561 is 16514437871882.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16894360575625 + 11923512865936 = 4110275^2 + 3453044^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28817873441561 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (28817873401561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14408936720780 + 14408936720781.

It is an arithmetic number, because the mean of its divisors is an integer number (14408936720781).

Almost surely, 2^{28817873441561} is an apocalyptic number.

It is an amenable number.

28817873441561 is a deficient number, since it is larger than the sum of its proper divisors (1).

28817873441561 is an equidigital number, since it uses as much as digits as its factorization.

28817873441561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72253440, while the sum is 65.

The spelling of 28817873441561 in words is "twenty-eight trillion, eight hundred seventeen billion, eight hundred seventy-three million, four hundred forty-one thousand, five hundred sixty-one".