257256929 has 4 divisors (see below), whose sum is σ = 258678420. Its totient is φ = 255835440.

The previous prime is 257256913. The next prime is 257256949. The reversal of 257256929 is 929652752.

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 54051904 + 203205025 = 7352^2 + 14255^2 .

It is a cyclic number.

It is not a de Polignac number, because 257256929 - 2⁴ = 257256913 is a prime.

It is a super-2 number, since 2×257256929² = 132362255037022082, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (257256949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 710474 + ... + 710835.

It is an arithmetic number, because the mean of its divisors is an integer number (64669605).

Almost surely, 2^257256929 is an apocalyptic number.

It is an amenable number.

257256929 is a deficient number, since it is larger than the sum of its proper divisors (1421491).

257256929 is a wasteful number, since it uses less digits than its factorization.

257256929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1421490.

The product of its digits is 680400, while the sum is 47.

The square root of 257256929 is about 16039.2309354283. The cubic root of 257256929 is about 635.9979175663.

The spelling of 257256929 in words is "two hundred fifty-seven million, two hundred fifty-six thousand, nine hundred twenty-nine".