8457257 has 4 divisors (see below), whose sum is σ = 8487636. Its totient is φ = 8426880.

The previous prime is 8457247. The next prime is 8457271. The reversal of 8457257 is 7527548.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2202256 + 6255001 = 1484^2 + 2501^2 .

It is a cyclic number.

It is not a de Polignac number, because 8457257 - 2¹⁰ = 8456233 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 8457257.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8457217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14768 + ... + 15329.

It is an arithmetic number, because the mean of its divisors is an integer number (2121909).

Almost surely, 2^8457257 is an apocalyptic number.

It is an amenable number.

8457257 is a deficient number, since it is larger than the sum of its proper divisors (30379).

8457257 is a wasteful number, since it uses less digits than its factorization.

8457257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30378.

The product of its digits is 78400, while the sum is 38.

The square root of 8457257 is about 2908.1363448092. The cubic root of 8457257 is about 203.7400973771.

The spelling of 8457257 in words is "eight million, four hundred fifty-seven thousand, two hundred fifty-seven".