257298749 has 4 divisors (see below), whose sum is σ = 257457564. Its totient is φ = 257139936.

The previous prime is 257298731. The next prime is 257298761. The reversal of 257298749 is 947892752.

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 138815524 + 118483225 = 11782^2 + 10885^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257298749 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 257298749.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257298719) 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, 76952 + ... + 80225.

It is an arithmetic number, because the mean of its divisors is an integer number (64364391).

Almost surely, 2^257298749 is an apocalyptic number.

It is an amenable number.

257298749 is a deficient number, since it is larger than the sum of its proper divisors (158815).

257298749 is a wasteful number, since it uses less digits than its factorization.

257298749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158814.

The product of its digits is 2540160, while the sum is 53.

The square root of 257298749 is about 16040.5345609178. The cubic root of 257298749 is about 636.0323785647.

The spelling of 257298749 in words is "two hundred fifty-seven million, two hundred ninety-eight thousand, seven hundred forty-nine".