165620563 has 4 divisors (see below), whose sum is σ = 169472248. Its totient is φ = 161768880.

The previous prime is 165620561. The next prime is 165620627. The reversal of 165620563 is 365026561.

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

It is a cyclic number.

It is not a de Polignac number, because 165620563 - 2¹ = 165620561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165620561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1925778 + ... + 1925863.

It is an arithmetic number, because the mean of its divisors is an integer number (42368062).

Almost surely, 2^165620563 is an apocalyptic number.

165620563 is a deficient number, since it is larger than the sum of its proper divisors (3851685).

165620563 is an equidigital number, since it uses as much as digits as its factorization.

165620563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3851684.

The product of its (nonzero) digits is 32400, while the sum is 34.

The square root of 165620563 is about 12869.3652912644. The cubic root of 165620563 is about 549.1674047080.

The spelling of 165620563 in words is "one hundred sixty-five million, six hundred twenty thousand, five hundred sixty-three".