128101 has 4 divisors (see below), whose sum is σ = 130572. Its totient is φ = 125632.

The previous prime is 128099. The next prime is 128111. The reversal of 128101 is 101821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 112225 + 15876 = 335^2 + 126^2 .

It is a cyclic number.

It is not a de Polignac number, because 128101 - 2¹ = 128099 is a prime.

It is an Ulam number.

It is a Duffinian number.

128101 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128111) 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, 1156 + ... + 1261.

It is an arithmetic number, because the mean of its divisors is an integer number (32643).

2¹²⁸¹⁰¹ is an apocalyptic number.

It is an amenable number.

128101 is a deficient number, since it is larger than the sum of its proper divisors (2471).

128101 is an equidigital number, since it uses as much as digits as its factorization.

128101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2470.

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 128101 is about 357.9120003576. The cubic root of 128101 is about 50.4100939303.

Adding to 128101 its reverse (101821), we get a palindrome (229922).

The spelling of 128101 in words is "one hundred twenty-eight thousand, one hundred one".