256423021706 has 8 divisors (see below), whose sum is σ = 395030060580. Its totient is φ = 124746334848.

The previous prime is 256423021663. The next prime is 256423021721. The reversal of 256423021706 is 607120324652.

It can be written as a sum of positive squares in 2 ways, for example, as 256348803481 + 74218225 = 506309^2 + 8615^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 256423021706.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1732587911 + ... + 1732588058.

Almost surely, 2^256423021706 is an apocalyptic number.

256423021706 is a deficient number, since it is larger than the sum of its proper divisors (138607038874).

256423021706 is a wasteful number, since it uses less digits than its factorization.

256423021706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3465176008.

The product of its (nonzero) digits is 120960, while the sum is 38.

The spelling of 256423021706 in words is "two hundred fifty-six billion, four hundred twenty-three million, twenty-one thousand, seven hundred six".