157811 has 4 divisors (see below), whose sum is σ = 167112. Its totient is φ = 148512.

The previous prime is 157799. The next prime is 157813. The reversal of 157811 is 118751.

157811 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 157811 - 2⁶ = 157747 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (157813) 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, 4625 + ... + 4658.

It is an arithmetic number, because the mean of its divisors is an integer number (41778).

2¹⁵⁷⁸¹¹ is an apocalyptic number.

157811 is a deficient number, since it is larger than the sum of its proper divisors (9301).

157811 is an equidigital number, since it uses as much as digits as its factorization.

157811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9300.

The product of its digits is 280, while the sum is 23.

The square root of 157811 is about 397.2543265970. The cubic root of 157811 is about 54.0396371079.

Subtracting from 157811 its reverse (118751), we obtain a triangular number (39060 = T₂₇₉).

The spelling of 157811 in words is "one hundred fifty-seven thousand, eight hundred eleven".