271561 has 4 divisors (see below), whose sum is σ = 283392. Its totient is φ = 259732.

The previous prime is 271553. The next prime is 271571. The reversal of 271561 is 165172.

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.

It is a cyclic number.

It is not a de Polignac number, because 271561 - 2³ = 271553 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

271561 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (271501) 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, 5881 + ... + 5926.

It is an arithmetic number, because the mean of its divisors is an integer number (70848).

2²⁷¹⁵⁶¹ is an apocalyptic number.

It is an amenable number.

271561 is a deficient number, since it is larger than the sum of its proper divisors (11831).

271561 is a wasteful number, since it uses less digits than its factorization.

271561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11830.

The product of its digits is 420, while the sum is 22.

The square root of 271561 is about 521.1151504226. The cubic root of 271561 is about 64.7573596679.

The spelling of 271561 in words is "two hundred seventy-one thousand, five hundred sixty-one".