135857 has 4 divisors (see below), whose sum is σ = 137280. Its totient is φ = 134436.

The previous prime is 135851. The next prime is 135859. The reversal of 135857 is 758531.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 758531 = 109 ⋅6959.

It is a cyclic number.

It is not a de Polignac number, because 135857 - 2⁴ = 135841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (135851) 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, 557 + ... + 762.

It is an arithmetic number, because the mean of its divisors is an integer number (34320).

2¹³⁵⁸⁵⁷ is an apocalyptic number.

It is an amenable number.

135857 is a deficient number, since it is larger than the sum of its proper divisors (1423).

135857 is a wasteful number, since it uses less digits than its factorization.

135857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1422.

The product of its digits is 4200, while the sum is 29.

The square root of 135857 is about 368.5878457030. The cubic root of 135857 is about 51.4076013124.

The spelling of 135857 in words is "one hundred thirty-five thousand, eight hundred fifty-seven".