256657441017407 has 4 divisors (see below), whose sum is σ = 257722409652576. Its totient is φ = 255592472382240.

The previous prime is 256657441017391. The next prime is 256657441017427. The reversal of 256657441017407 is 704710144756652.

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

It is a cyclic number.

It is not a de Polignac number, because 256657441017407 - 2⁴ = 256657441017391 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 (256657441017427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 532484317223 + ... + 532484317704.

It is an arithmetic number, because the mean of its divisors is an integer number (64430602413144).

Almost surely, 2^{256657441017407} is an apocalyptic number.

256657441017407 is a deficient number, since it is larger than the sum of its proper divisors (1064968635169).

256657441017407 is a wasteful number, since it uses less digits than its factorization.

256657441017407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1064968635168.

The product of its (nonzero) digits is 39513600, while the sum is 59.

The spelling of 256657441017407 in words is "two hundred fifty-six trillion, six hundred fifty-seven billion, four hundred forty-one million, seventeen thousand, four hundred seven".