257278577663 has 4 divisors (see below), whose sum is σ = 257920170528. Its totient is φ = 256636984800.

The previous prime is 257278577659. The next prime is 257278577753. The reversal of 257278577663 is 366775872752.

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 257278577663 - 2² = 257278577659 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 257278577663.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257278577603) 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, 320795831 + ... + 320796632.

It is an arithmetic number, because the mean of its divisors is an integer number (64480042632).

Almost surely, 2^257278577663 is an apocalyptic number.

257278577663 is a deficient number, since it is larger than the sum of its proper divisors (641592865).

257278577663 is an equidigital number, since it uses as much as digits as its factorization.

257278577663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 641592864.

The product of its digits is 207446400, while the sum is 65.

The spelling of 257278577663 in words is "two hundred fifty-seven billion, two hundred seventy-eight million, five hundred seventy-seven thousand, six hundred sixty-three".