28128355769 has 2 divisors, whose sum is σ = 28128355770. Its totient is φ = 28128355768.

The previous prime is 28128355757. The next prime is 28128355789. The reversal of 28128355769 is 96755382182.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28052230144 + 76125625 = 167488^2 + 8725^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28128355769 is a prime.

It is a super-2 number, since 2×28128355769² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28128355709) 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, 14064177884 + 14064177885.

It is an arithmetic number, because the mean of its divisors is an integer number (14064177885).

Almost surely, 2^28128355769 is an apocalyptic number.

It is an amenable number.

28128355769 is a deficient number, since it is larger than the sum of its proper divisors (1).

28128355769 is an equidigital number, since it uses as much as digits as its factorization.

28128355769 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7257600, while the sum is 56.

The spelling of 28128355769 in words is "twenty-eight billion, one hundred twenty-eight million, three hundred fifty-five thousand, seven hundred sixty-nine".