163605621 has 16 divisors (see below), whose sum is σ = 225529920. Its totient is φ = 105425280.

The previous prime is 163605613. The next prime is 163605667. The reversal of 163605621 is 126506361.

It is not a de Polignac number, because 163605621 - 2³ = 163605613 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (163605691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7306 + ... + 19508.

It is an arithmetic number, because the mean of its divisors is an integer number (14095620).

Almost surely, 2^163605621 is an apocalyptic number.

It is an amenable number.

163605621 is a deficient number, since it is larger than the sum of its proper divisors (61924299).

163605621 is a wasteful number, since it uses less digits than its factorization.

163605621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12356.

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 163605621 is about 12790.8412936757. The cubic root of 163605621 is about 546.9312523404.

The spelling of 163605621 in words is "one hundred sixty-three million, six hundred five thousand, six hundred twenty-one".