256138 has 8 divisors (see below), whose sum is σ = 389088. Its totient is φ = 126444.

The previous prime is 256133. The next prime is 256147. The reversal of 256138 is 831652.

It is a happy number.

256138 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not an unprimeable number, because it can be changed into a prime (256133) 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, 606 + ... + 937.

It is an arithmetic number, because the mean of its divisors is an integer number (48636).

2²⁵⁶¹³⁸ is an apocalyptic number.

256138 is a deficient number, since it is larger than the sum of its proper divisors (132950).

256138 is a wasteful number, since it uses less digits than its factorization.

256138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1628.

The product of its digits is 1440, while the sum is 25.

The square root of 256138 is about 506.1007804776. The cubic root of 256138 is about 63.5074494743.

The spelling of 256138 in words is "two hundred fifty-six thousand, one hundred thirty-eight".