128725919 has 8 divisors (see below), whose sum is σ = 151861248. Its totient is φ = 106777080.

The previous prime is 128725913. The next prime is 128725939. The reversal of 128725919 is 919527821.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128725919 is a prime.

It is a super-2 number, since 2×128725919² = 33140724444789122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 128725919.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128725913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 296387 + ... + 296820.

It is an arithmetic number, because the mean of its divisors is an integer number (18982656).

Almost surely, 2^128725919 is an apocalyptic number.

128725919 is a deficient number, since it is larger than the sum of its proper divisors (23135329).

128725919 is an equidigital number, since it uses as much as digits as its factorization.

128725919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 593245.

The product of its digits is 90720, while the sum is 44.

The square root of 128725919 is about 11345.7445326431. The cubic root of 128725919 is about 504.9193335847.

The spelling of 128725919 in words is "one hundred twenty-eight million, seven hundred twenty-five thousand, nine hundred nineteen".