128251 has 4 divisors (see below), whose sum is σ = 128992. Its totient is φ = 127512.

The previous prime is 128239. The next prime is 128257. The reversal of 128251 is 152821.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 128251 - 2⁹ = 127739 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128257) 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 3 ways as a sum of consecutive naturals, for example, 46 + ... + 508.

It is an arithmetic number, because the mean of its divisors is an integer number (32248).

2¹²⁸²⁵¹ is an apocalyptic number.

128251 is a deficient number, since it is larger than the sum of its proper divisors (741).

128251 is an equidigital number, since it uses as much as digits as its factorization.

128251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 740.

The product of its digits is 160, while the sum is 19.

The square root of 128251 is about 358.1214877664. The cubic root of 128251 is about 50.4297621728.

The spelling of 128251 in words is "one hundred twenty-eight thousand, two hundred fifty-one".