165563 has 4 divisors (see below), whose sum is σ = 175320. Its totient is φ = 155808.

The previous prime is 165559. The next prime is 165569. The reversal of 165563 is 365561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 365561 = 7 ⋅52223.

It is a cyclic number.

It is not a de Polignac number, because 165563 - 2² = 165559 is a prime.

It is a super-2 number, since 2×165563² = 54822213938, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (165569) 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, 4853 + ... + 4886.

It is an arithmetic number, because the mean of its divisors is an integer number (43830).

2¹⁶⁵⁵⁶³ is an apocalyptic number.

165563 is a deficient number, since it is larger than the sum of its proper divisors (9757).

165563 is an equidigital number, since it uses as much as digits as its factorization.

165563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9756.

The product of its digits is 2700, while the sum is 26.

The square root of 165563 is about 406.8943351781. The cubic root of 165563 is about 54.9103774553.

The spelling of 165563 in words is "one hundred sixty-five thousand, five hundred sixty-three".