257540781079 has 4 divisors (see below), whose sum is σ = 257545474560. Its totient is φ = 257536087600.

The previous prime is 257540781077. The next prime is 257540781109. The reversal of 257540781079 is 970187045752.

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 257540781079 - 2¹ = 257540781077 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 (257540781077) 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, 2263447 + ... + 2374504.

It is an arithmetic number, because the mean of its divisors is an integer number (64386368640).

Almost surely, 2^257540781079 is an apocalyptic number.

257540781079 is a deficient number, since it is larger than the sum of its proper divisors (4693481).

257540781079 is an equidigital number, since it uses as much as digits as its factorization.

257540781079 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4693480.

The product of its (nonzero) digits is 4939200, while the sum is 55.

The spelling of 257540781079 in words is "two hundred fifty-seven billion, five hundred forty million, seven hundred eighty-one thousand, seventy-nine".