257487 has 4 divisors (see below), whose sum is σ = 343320. Its totient is φ = 171656.

The previous prime is 257473. The next prime is 257489. The reversal of 257487 is 784752.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257487 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257489) 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, 42912 + ... + 42917.

It is an arithmetic number, because the mean of its divisors is an integer number (85830).

2²⁵⁷⁴⁸⁷ is an apocalyptic number.

257487 is a deficient number, since it is larger than the sum of its proper divisors (85833).

257487 is an equidigital number, since it uses as much as digits as its factorization.

257487 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85832.

The product of its digits is 15680, while the sum is 33.

The square root of 257487 is about 507.4317688123. The cubic root of 257487 is about 63.6187457104.

The spelling of 257487 in words is "two hundred fifty-seven thousand, four hundred eighty-seven".