128319672121 has 2 divisors, whose sum is σ = 128319672122. Its totient is φ = 128319672120.

The previous prime is 128319672109. The next prime is 128319672133. The reversal of 128319672121 is 121276913821.

It is a balanced prime because it is at equal distance from previous prime (128319672109) and next prime (128319672133).

It can be written as a sum of positive squares in only one way, i.e., 70683666496 + 57636005625 = 265864^2 + 240075^2 .

It is a cyclic number.

It is not a de Polignac number, because 128319672121 - 2¹⁵ = 128319639353 is a prime.

It is not a weakly prime, because it can be changed into another prime (128319672161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64159836060 + 64159836061.

It is an arithmetic number, because the mean of its divisors is an integer number (64159836061).

Almost surely, 2^128319672121 is an apocalyptic number.

It is an amenable number.

128319672121 is a deficient number, since it is larger than the sum of its proper divisors (1).

128319672121 is an equidigital number, since it uses as much as digits as its factorization.

128319672121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72576, while the sum is 43.

The spelling of 128319672121 in words is "one hundred twenty-eight billion, three hundred nineteen million, six hundred seventy-two thousand, one hundred twenty-one".