128149 has 4 divisors (see below), whose sum is σ = 146464. Its totient is φ = 109836.

The previous prime is 128147. The next prime is 128153. The reversal of 128149 is 941821.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 941821 = 191 ⋅4931.

It is a cyclic number.

It is not a de Polignac number, because 128149 - 2¹ = 128147 is a prime.

It is a Duffinian number.

128149 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128147) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9147 + ... + 9160.

It is an arithmetic number, because the mean of its divisors is an integer number (36616).

2¹²⁸¹⁴⁹ is an apocalyptic number.

It is an amenable number.

128149 is a deficient number, since it is larger than the sum of its proper divisors (18315).

128149 is an equidigital number, since it uses as much as digits as its factorization.

128149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18314.

The product of its digits is 576, while the sum is 25.

The square root of 128149 is about 357.9790496663. The cubic root of 128149 is about 50.4163894376.

The spelling of 128149 in words is "one hundred twenty-eight thousand, one hundred forty-nine".