128976909 has 32 divisors (see below), whose sum is σ = 188457984. Its totient is φ = 78140160.

The previous prime is 128976889. The next prime is 128976919. The reversal of 128976909 is 909679821.

It is a happy number.

It is not a de Polignac number, because 128976909 - 2⁷ = 128976781 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128976919) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 225594 + ... + 226164.

It is an arithmetic number, because the mean of its divisors is an integer number (5889312).

Almost surely, 2^128976909 is an apocalyptic number.

It is an amenable number.

128976909 is a deficient number, since it is larger than the sum of its proper divisors (59481075).

128976909 is a wasteful number, since it uses less digits than its factorization.

128976909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 737.

The product of its (nonzero) digits is 489888, while the sum is 51.

The square root of 128976909 is about 11356.8001215131. The cubic root of 128976909 is about 505.2472847016.

The spelling of 128976909 in words is "one hundred twenty-eight million, nine hundred seventy-six thousand, nine hundred nine".