163988321 has 16 divisors (see below), whose sum is σ = 195953664. Its totient is φ = 134182224.

The previous prime is 163988309. The next prime is 163988327. The reversal of 163988321 is 123889361.

It is a cyclic number.

It is not a de Polignac number, because 163988321 - 2¹⁴ = 163971937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (163988327) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 145466 + ... + 146588.

It is an arithmetic number, because the mean of its divisors is an integer number (12247104).

Almost surely, 2^163988321 is an apocalyptic number.

It is an amenable number.

163988321 is a deficient number, since it is larger than the sum of its proper divisors (31965343).

163988321 is a wasteful number, since it uses less digits than its factorization.

163988321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2060.

The product of its digits is 62208, while the sum is 41.

The square root of 163988321 is about 12805.7924784060. The cubic root of 163988321 is about 547.3573738004.

The spelling of 163988321 in words is "one hundred sixty-three million, nine hundred eighty-eight thousand, three hundred twenty-one".