257640667020827 has 8 divisors (see below), whose sum is σ = 265556633879856. Its totient is φ = 249812169409152.

The previous prime is 257640667020817. The next prime is 257640667020881. The reversal of 257640667020827 is 728020766046752.

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

It is a cyclic number.

It is not a de Polignac number, because 257640667020827 - 2⁴ = 257640667020811 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 257640667020827.

It is not an unprimeable number, because it can be changed into a prime (257640667020817) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21867305858 + ... + 21867317639.

It is an arithmetic number, because the mean of its divisors is an integer number (33194579234982).

Almost surely, 2^{257640667020827} is an apocalyptic number.

257640667020827 is a deficient number, since it is larger than the sum of its proper divisors (7915966859029).

257640667020827 is a wasteful number, since it uses less digits than its factorization.

257640667020827 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43734623677.

The product of its (nonzero) digits is 94832640, while the sum is 62.

The spelling of 257640667020827 in words is "two hundred fifty-seven trillion, six hundred forty billion, six hundred sixty-seven million, twenty thousand, eight hundred twenty-seven".