158705 has 4 divisors (see below), whose sum is σ = 190452. Its totient is φ = 126960.

The previous prime is 158699. The next prime is 158731. The reversal of 158705 is 507851.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 507851 = 19 ⋅26729.

It can be written as a sum of positive squares in 2 ways, for example, as 85264 + 73441 = 292^2 + 271^2 .

It is not a de Polignac number, because 158705 - 2⁸ = 158449 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15866 + ... + 15875.

It is an arithmetic number, because the mean of its divisors is an integer number (47613).

2¹⁵⁸⁷⁰⁵ is an apocalyptic number.

It is an amenable number.

158705 is a deficient number, since it is larger than the sum of its proper divisors (31747).

158705 is an equidigital number, since it uses as much as digits as its factorization.

158705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31746.

The product of its (nonzero) digits is 1400, while the sum is 26.

The square root of 158705 is about 398.3779612378. The cubic root of 158705 is about 54.1414899433.

The spelling of 158705 in words is "one hundred fifty-eight thousand, seven hundred five".