256218135688279 has 4 divisors (see below), whose sum is σ = 271289790728784. Its totient is φ = 241146480647776.

The previous prime is 256218135688261. The next prime is 256218135688301. The reversal of 256218135688279 is 972886531812652.

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

It is not a de Polignac number, because 256218135688279 - 2¹⁵ = 256218135655511 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 (256218135688259) 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, 7535827520227 + ... + 7535827520260.

It is an arithmetic number, because the mean of its divisors is an integer number (67822447682196).

Almost surely, 2^{256218135688279} is an apocalyptic number.

256218135688279 is a deficient number, since it is larger than the sum of its proper divisors (15071655040505).

256218135688279 is a wasteful number, since it uses less digits than its factorization.

256218135688279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15071655040504.

The product of its digits is 696729600, while the sum is 73.

The spelling of 256218135688279 in words is "two hundred fifty-six trillion, two hundred eighteen billion, one hundred thirty-five million, six hundred eighty-eight thousand, two hundred seventy-nine".