28120068869 has 2 divisors, whose sum is σ = 28120068870. Its totient is φ = 28120068868.

The previous prime is 28120068859. The next prime is 28120068877. The reversal of 28120068869 is 96886002182.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25237452769 + 2882616100 = 158863^2 + 53690^2 .

It is a cyclic number.

It is not a de Polignac number, because 28120068869 - 2¹⁶ = 28120003333 is a prime.

It is a super-2 number, since 2×28120068869² (a number of 22 digits) contains 22 as substring.

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 (28120068829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14060034434 + 14060034435.

It is an arithmetic number, because the mean of its divisors is an integer number (14060034435).

Almost surely, 2^28120068869 is an apocalyptic number.

It is an amenable number.

28120068869 is a deficient number, since it is larger than the sum of its proper divisors (1).

28120068869 is an equidigital number, since it uses as much as digits as its factorization.

28120068869 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 663552, while the sum is 50.

The spelling of 28120068869 in words is "twenty-eight billion, one hundred twenty million, sixty-eight thousand, eight hundred sixty-nine".