257138135 has 4 divisors (see below), whose sum is σ = 308565768. Its totient is φ = 205710504.

The previous prime is 257138131. The next prime is 257138159. The reversal of 257138135 is 531831752.

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

It is a cyclic number.

It is not a de Polignac number, because 257138135 - 2² = 257138131 is a prime.

It is a super-2 number, since 2×257138135² = 132240040942556450, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 257138095 and 257138104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257138131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25713809 + ... + 25713818.

It is an arithmetic number, because the mean of its divisors is an integer number (77141442).

Almost surely, 2^257138135 is an apocalyptic number.

257138135 is a deficient number, since it is larger than the sum of its proper divisors (51427633).

257138135 is an equidigital number, since it uses as much as digits as its factorization.

257138135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51427632.

The product of its digits is 25200, while the sum is 35.

The square root of 257138135 is about 16035.5272753970. The cubic root of 257138135 is about 635.9000071890.

Adding to 257138135 its reverse (531831752), we get a palindrome (788969887).

The spelling of 257138135 in words is "two hundred fifty-seven million, one hundred thirty-eight thousand, one hundred thirty-five".