21232012321 has 16 divisors (see below), whose sum is σ = 23490028800. Its totient is φ = 19181691984.

The previous prime is 21232012301. The next prime is 21232012337. The reversal of 21232012321 is 12321023212.

It is not a de Polignac number, because 21232012321 - 2¹¹ = 21232010273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21232012301) 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, 450 + ... + 206068.

It is an arithmetic number, because the mean of its divisors is an integer number (1468126800).

Almost surely, 2^21232012321 is an apocalyptic number.

It is an amenable number.

21232012321 is a deficient number, since it is larger than the sum of its proper divisors (2258016479).

21232012321 is an equidigital number, since it uses as much as digits as its factorization.

21232012321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205705 (or 205679 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21232012321 its reverse (12321023212), we get a palindrome (33553035533).

The spelling of 21232012321 in words is "twenty-one billion, two hundred thirty-two million, twelve thousand, three hundred twenty-one".