165021103 has 4 divisors (see below), whose sum is σ = 177715048. Its totient is φ = 152327160.

The previous prime is 165021097. The next prime is 165021121. The reversal of 165021103 is 301120561.

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 165021103 - 2⁹ = 165020591 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 (165021163) 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, 6346953 + ... + 6346978.

It is an arithmetic number, because the mean of its divisors is an integer number (44428762).

Almost surely, 2^165021103 is an apocalyptic number.

165021103 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

165021103 is a deficient number, since it is larger than the sum of its proper divisors (12693945).

165021103 is a wasteful number, since it uses less digits than its factorization.

165021103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12693944.

The product of its (nonzero) digits is 180, while the sum is 19.

The square root of 165021103 is about 12846.0539855630. The cubic root of 165021103 is about 548.5040372510.

Adding to 165021103 its reverse (301120561), we get a palindrome (466141664).

The spelling of 165021103 in words is "one hundred sixty-five million, twenty-one thousand, one hundred three".