128779125 has 16 divisors (see below), whose sum is σ = 214289088. Its totient is φ = 68682000.

The previous prime is 128779121. The next prime is 128779127. The reversal of 128779125 is 521977821.

It is not a de Polignac number, because 128779125 - 2² = 128779121 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128779121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 171331 + ... + 172080.

It is an arithmetic number, because the mean of its divisors is an integer number (13393068).

Almost surely, 2^128779125 is an apocalyptic number.

128779125 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128779125 is a deficient number, since it is larger than the sum of its proper divisors (85509963).

128779125 is an equidigital number, since it uses as much as digits as its factorization.

128779125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343429 (or 343419 counting only the distinct ones).

The product of its digits is 70560, while the sum is 42.

The square root of 128779125 is about 11348.0890461787. The cubic root of 128779125 is about 504.9888897337.

The spelling of 128779125 in words is "one hundred twenty-eight million, seven hundred seventy-nine thousand, one hundred twenty-five".