165531 has 8 divisors (see below), whose sum is σ = 230400. Its totient is φ = 105512.

The previous prime is 165527. The next prime is 165533. The reversal of 165531 is 135561.

165531 = 36² + 37² + ... + 81².

It is a happy number.

165531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 165531 - 2² = 165527 is a prime.

It is a super-2 number, since 2×165531² = 54801023922, which contains 22 as substring.

It is a plaindrome in base 14.

It is a junction number, because it is equal to n+sod(n) for n = 165498 and 165507.

It is not an unprimeable number, because it can be changed into a prime (165533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1131 + ... + 1268.

It is an arithmetic number, because the mean of its divisors is an integer number (28800).

2¹⁶⁵⁵³¹ is an apocalyptic number.

165531 is a deficient number, since it is larger than the sum of its proper divisors (64869).

165531 is a wasteful number, since it uses less digits than its factorization.

165531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2425.

The product of its digits is 450, while the sum is 21.

The square root of 165531 is about 406.8550110297. The cubic root of 165531 is about 54.9068395366.

It can be divided in two parts, 165 and 531, that added together give a palindrome (696).

The spelling of 165531 in words is "one hundred sixty-five thousand, five hundred thirty-one".