128247878789 has 2 divisors, whose sum is σ = 128247878790. Its totient is φ = 128247878788.

The previous prime is 128247878777. The next prime is 128247878791. The reversal of 128247878789 is 987878742821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70763980225 + 57483898564 = 266015^2 + 239758^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128247878789 is a prime.

It is a super-2 number, since 2×128247878789² (a number of 23 digits) contains 22 as substring.

Together with 128247878791, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128247878989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64123939394 + 64123939395.

It is an arithmetic number, because the mean of its divisors is an integer number (64123939395).

Almost surely, 2^128247878789 is an apocalyptic number.

It is an amenable number.

128247878789 is a deficient number, since it is larger than the sum of its proper divisors (1).

128247878789 is an equidigital number, since it uses as much as digits as its factorization.

128247878789 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 202309632, while the sum is 71.

The spelling of 128247878789 in words is "one hundred twenty-eight billion, two hundred forty-seven million, eight hundred seventy-eight thousand, seven hundred eighty-nine".