163121321 has 8 divisors (see below), whose sum is σ = 178071744. Its totient is φ = 148191120.

The previous prime is 163121303. The next prime is 163121351. The reversal of 163121321 is 123121361.

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

It is not a de Polignac number, because 163121321 - 2¹⁰ = 163120297 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 163121293 and 163121302.

It is not an unprimeable number, because it can be changed into a prime (163121351) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15455 + ... + 23771.

It is an arithmetic number, because the mean of its divisors is an integer number (22258968).

Almost surely, 2^163121321 is an apocalyptic number.

163121321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

163121321 is a deficient number, since it is larger than the sum of its proper divisors (14950423).

163121321 is a wasteful number, since it uses less digits than its factorization.

163121321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10111.

The product of its digits is 216, while the sum is 20.

The square root of 163121321 is about 12771.8957480869. The cubic root of 163121321 is about 546.3910496334.

Adding to 163121321 its reverse (123121361), we get a palindrome (286242682).

The spelling of 163121321 in words is "one hundred sixty-three million, one hundred twenty-one thousand, three hundred twenty-one".