163720808903 has 4 divisors (see below), whose sum is σ = 163771048680. Its totient is φ = 163670569128.

The previous prime is 163720808887. The next prime is 163720808929. The reversal of 163720808903 is 309808027361.

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 163720808903 - 2⁴ = 163720808887 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 (163720808963) 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, 25115000 + ... + 25121517.

It is an arithmetic number, because the mean of its divisors is an integer number (40942762170).

Almost surely, 2^163720808903 is an apocalyptic number.

163720808903 is a deficient number, since it is larger than the sum of its proper divisors (50239777).

163720808903 is an equidigital number, since it uses as much as digits as its factorization.

163720808903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50239776.

The product of its (nonzero) digits is 435456, while the sum is 47.

The spelling of 163720808903 in words is "one hundred sixty-three billion, seven hundred twenty million, eight hundred eight thousand, nine hundred three".