128949 has 8 divisors (see below), whose sum is σ = 175392. Its totient is φ = 84240.

The previous prime is 128941. The next prime is 128951. The reversal of 128949 is 949821.

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

It is not a de Polignac number, because 128949 - 2³ = 128941 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 247 + ... + 564.

It is an arithmetic number, because the mean of its divisors is an integer number (21924).

2¹²⁸⁹⁴⁹ is an apocalyptic number.

It is an amenable number.

128949 is a deficient number, since it is larger than the sum of its proper divisors (46443).

128949 is an equidigital number, since it uses as much as digits as its factorization.

128949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 867.

The product of its digits is 5184, while the sum is 33.

The square root of 128949 is about 359.0946950318. The cubic root of 128949 is about 50.5210838995.

The spelling of 128949 in words is "one hundred twenty-eight thousand, nine hundred forty-nine".