128872123 has 2 divisors, whose sum is σ = 128872124. Its totient is φ = 128872122.

The previous prime is 128872109. The next prime is 128872127. The reversal of 128872123 is 321278821.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 128872123 - 2²¹ = 126774971 is a prime.

It is not a weakly prime, because it can be changed into another prime (128872127) 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, 64436061 + 64436062.

It is an arithmetic number, because the mean of its divisors is an integer number (64436062).

Almost surely, 2^128872123 is an apocalyptic number.

128872123 is a deficient number, since it is larger than the sum of its proper divisors (1).

128872123 is an equidigital number, since it uses as much as digits as its factorization.

128872123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10752, while the sum is 34.

The square root of 128872123 is about 11352.1858247652. The cubic root of 128872123 is about 505.1104199287.

The spelling of 128872123 in words is "one hundred twenty-eight million, eight hundred seventy-two thousand, one hundred twenty-three".