163938505 has 4 divisors (see below), whose sum is σ = 196726212. Its totient is φ = 131150800.

The previous prime is 163938499. The next prime is 163938539. The reversal of 163938505 is 505839361.

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

It can be written as a sum of positive squares in 2 ways, for example, as 130576329 + 33362176 = 11427^2 + 5776^2 .

It is not a de Polignac number, because 163938505 - 2²⁵ = 130384073 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16393846 + ... + 16393855.

It is an arithmetic number, because the mean of its divisors is an integer number (49181553).

Almost surely, 2^163938505 is an apocalyptic number.

It is an amenable number.

163938505 is a deficient number, since it is larger than the sum of its proper divisors (32787707).

163938505 is an equidigital number, since it uses as much as digits as its factorization.

163938505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32787706.

The product of its (nonzero) digits is 97200, while the sum is 40.

The square root of 163938505 is about 12803.8472733784. The cubic root of 163938505 is about 547.3019431936.

The spelling of 163938505 in words is "one hundred sixty-three million, nine hundred thirty-eight thousand, five hundred five".