162581 has 4 divisors (see below), whose sum is σ = 163392. Its totient is φ = 161772.

The previous prime is 162577. The next prime is 162593. The reversal of 162581 is 185261.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 185261 = 229 ⋅809.

It is a cyclic number.

It is not a de Polignac number, because 162581 - 2² = 162577 is a prime.

It is a super-2 number, since 2×162581² = 52865163122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (162881) 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, 146 + ... + 588.

It is an arithmetic number, because the mean of its divisors is an integer number (40848).

2¹⁶²⁵⁸¹ is an apocalyptic number.

It is an amenable number.

162581 is a deficient number, since it is larger than the sum of its proper divisors (811).

162581 is an equidigital number, since it uses as much as digits as its factorization.

162581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 810.

The product of its digits is 480, while the sum is 23.

The square root of 162581 is about 403.2133430332. The cubic root of 162581 is about 54.5787096032.

The spelling of 162581 in words is "one hundred sixty-two thousand, five hundred eighty-one".