161571 has 4 divisors (see below), whose sum is σ = 215432. Its totient is φ = 107712.

The previous prime is 161569. The next prime is 161573. The reversal of 161571 is 175161.

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

It is an interprime number because it is at equal distance from previous prime (161569) and next prime (161573).

It is not a de Polignac number, because 161571 - 2¹ = 161569 is a prime.

It is a super-2 number, since 2×161571² = 52210376082, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161573) 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, 26926 + ... + 26931.

It is an arithmetic number, because the mean of its divisors is an integer number (53858).

2¹⁶¹⁵⁷¹ is an apocalyptic number.

161571 is a deficient number, since it is larger than the sum of its proper divisors (53861).

161571 is an equidigital number, since it uses as much as digits as its factorization.

161571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53860.

The product of its digits is 210, while the sum is 21.

The square root of 161571 is about 401.9589531283. The cubic root of 161571 is about 54.4654552007.

The spelling of 161571 in words is "one hundred sixty-one thousand, five hundred seventy-one".