256143 has 4 divisors (see below), whose sum is σ = 341528. Its totient is φ = 170760.

The previous prime is 256133. The next prime is 256147. The reversal of 256143 is 341652.

It is a happy number.

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

It is not a de Polignac number, because 256143 - 2⁶ = 256079 is a prime.

It is a D-number.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

256143 is a lucky number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 256143.

It is not an unprimeable number, because it can be changed into a prime (256147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42688 + ... + 42693.

It is an arithmetic number, because the mean of its divisors is an integer number (85382).

2²⁵⁶¹⁴³ is an apocalyptic number.

256143 is a deficient number, since it is larger than the sum of its proper divisors (85385).

256143 is an equidigital number, since it uses as much as digits as its factorization.

256143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85384.

The product of its digits is 720, while the sum is 21.

The square root of 256143 is about 506.1057201811. The cubic root of 256143 is about 63.5078627088.

Adding to 256143 its reverse (341652), we get a palindrome (597795).

The spelling of 256143 in words is "two hundred fifty-six thousand, one hundred forty-three".