165520103 has 4 divisors (see below), whose sum is σ = 189165840. Its totient is φ = 141874368.

The previous prime is 165520049. The next prime is 165520111. The reversal of 165520103 is 301025561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 301025561 = 107 ⋅2813323.

It is a cyclic number.

It is not a de Polignac number, because 165520103 - 2¹² = 165516007 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165520133) 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, 11822858 + ... + 11822871.

It is an arithmetic number, because the mean of its divisors is an integer number (47291460).

Almost surely, 2^165520103 is an apocalyptic number.

165520103 is a deficient number, since it is larger than the sum of its proper divisors (23645737).

165520103 is an equidigital number, since it uses as much as digits as its factorization.

165520103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23645736.

The product of its (nonzero) digits is 900, while the sum is 23.

The square root of 165520103 is about 12865.4616318265. The cubic root of 165520103 is about 549.0563466066.

Adding to 165520103 its reverse (301025561), we get a palindrome (466545664).

The spelling of 165520103 in words is "one hundred sixty-five million, five hundred twenty thousand, one hundred three".