163640305 has 8 divisors (see below), whose sum is σ = 196440552. Its totient is φ = 130864128.

The previous prime is 163640273. The next prime is 163640333. The reversal of 163640305 is 503046361.

It can be written as a sum of positive squares in 4 ways, for example, as 5041 + 163635264 = 71^2 + 12792^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 163640305 - 2⁵ = 163640273 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16849 + ... + 24721.

It is an arithmetic number, because the mean of its divisors is an integer number (24555069).

Almost surely, 2^163640305 is an apocalyptic number.

It is an amenable number.

163640305 is a deficient number, since it is larger than the sum of its proper divisors (32800247).

163640305 is an equidigital number, since it uses as much as digits as its factorization.

163640305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12035.

The product of its (nonzero) digits is 6480, while the sum is 28.

The square root of 163640305 is about 12792.1970356933. The cubic root of 163640305 is about 546.9698989816.

Adding to 163640305 its reverse (503046361), we get a palindrome (666686666).

The spelling of 163640305 in words is "one hundred sixty-three million, six hundred forty thousand, three hundred five".