42811 has 4 divisors (see below), whose sum is σ = 44224. Its totient is φ = 41400.

The previous prime is 42797. The next prime is 42821. The reversal of 42811 is 11824.

It is a happy number.

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 42811 - 2⁷ = 42683 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (42821) 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, 660 + ... + 721.

It is an arithmetic number, because the mean of its divisors is an integer number (11056).

2⁴²⁸¹¹ is an apocalyptic number.

42811 is a deficient number, since it is larger than the sum of its proper divisors (1413).

42811 is a wasteful number, since it uses less digits than its factorization.

42811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1412.

The product of its digits is 64, while the sum is 16.

The square root of 42811 is about 206.9081922013. The cubic root of 42811 is about 34.9825763616.

Adding to 42811 its product of digits (64), we get a cube (42875 = 35³).

The spelling of 42811 in words is "forty-two thousand, eight hundred eleven".