257561047 has 2 divisors, whose sum is σ = 257561048. Its totient is φ = 257561046.

The previous prime is 257561021. The next prime is 257561053. The reversal of 257561047 is 740165752.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 257561047 - 2¹¹ = 257558999 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 257560997 and 257561015.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257561077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128780523 + 128780524.

It is an arithmetic number, because the mean of its divisors is an integer number (128780524).

Almost surely, 2^257561047 is an apocalyptic number.

257561047 is a deficient number, since it is larger than the sum of its proper divisors (1).

257561047 is an equidigital number, since it uses as much as digits as its factorization.

257561047 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58800, while the sum is 37.

The square root of 257561047 is about 16048.7085773280. The cubic root of 257561047 is about 636.2484352732.

The spelling of 257561047 in words is "two hundred fifty-seven million, five hundred sixty-one thousand, forty-seven".