128989725 has 12 divisors (see below), whose sum is σ = 213263136. Its totient is φ = 68794480.

The previous prime is 128989717. The next prime is 128989739. The reversal of 128989725 is 527989821.

It is not a de Polignac number, because 128989725 - 2³ = 128989717 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 859857 + ... + 860006.

It is an arithmetic number, because the mean of its divisors is an integer number (17771928).

Almost surely, 2^128989725 is an apocalyptic number.

128989725 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128989725 is a deficient number, since it is larger than the sum of its proper divisors (84273411).

128989725 is a wasteful number, since it uses less digits than its factorization.

128989725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1719876 (or 1719871 counting only the distinct ones).

The product of its digits is 725760, while the sum is 51.

The square root of 128989725 is about 11357.3643509399. The cubic root of 128989725 is about 505.2640190529.

The spelling of 128989725 in words is "one hundred twenty-eight million, nine hundred eighty-nine thousand, seven hundred twenty-five".