256929993577 has 4 divisors (see below), whose sum is σ = 258654356100. Its totient is φ = 255205631056.

The previous prime is 256929993563. The next prime is 256929993583. The reversal of 256929993577 is 775399929652.

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

It can be written as a sum of positive squares in 2 ways, for example, as 38770003801 + 218159989776 = 196901^2 + 467076^2 .

It is a cyclic number.

It is not a de Polignac number, because 256929993577 - 2¹⁹ = 256929469289 is a prime.

It is a super-2 number, since 2×256929993577² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256929999577) 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, 862181038 + ... + 862181335.

It is an arithmetic number, because the mean of its divisors is an integer number (64663589025).

Almost surely, 2^256929993577 is an apocalyptic number.

It is an amenable number.

256929993577 is a deficient number, since it is larger than the sum of its proper divisors (1724362523).

256929993577 is a wasteful number, since it uses less digits than its factorization.

256929993577 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1724362522.

The product of its digits is 578680200, while the sum is 73.

The spelling of 256929993577 in words is "two hundred fifty-six billion, nine hundred twenty-nine million, nine hundred ninety-three thousand, five hundred seventy-seven".