165993663803 has 4 divisors (see below), whose sum is σ = 181083996888. Its totient is φ = 150903330720.

The previous prime is 165993663757. The next prime is 165993663833. The reversal of 165993663803 is 308366399561.

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 165993663803 - 2³⁰ = 164919921979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165993663833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7545166526 + ... + 7545166547.

It is an arithmetic number, because the mean of its divisors is an integer number (45270999222).

Almost surely, 2^165993663803 is an apocalyptic number.

165993663803 is a deficient number, since it is larger than the sum of its proper divisors (15090333085).

165993663803 is a wasteful number, since it uses less digits than its factorization.

165993663803 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15090333084.

The product of its (nonzero) digits is 18895680, while the sum is 59.

The spelling of 165993663803 in words is "one hundred sixty-five billion, nine hundred ninety-three million, six hundred sixty-three thousand, eight hundred three".