21000023232321 has 64 divisors (see below), whose sum is σ = 33810429542400. Its totient is φ = 11338827257856.

The previous prime is 21000023232317. The next prime is 21000023232323. The reversal of 21000023232321 is 12323232000012.

It is a happy number.

It is not a de Polignac number, because 21000023232321 - 2² = 21000023232317 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (21000023232323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 570123121 + ... + 570159953.

It is an arithmetic number, because the mean of its divisors is an integer number (528287961600).

Almost surely, 2^{21000023232321} is an apocalyptic number.

21000023232321 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21000023232321 is a deficient number, since it is larger than the sum of its proper divisors (12810406310079).

21000023232321 is a wasteful number, since it uses less digits than its factorization.

21000023232321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56838.

The product of its (nonzero) digits is 864, while the sum is 21.

Adding to 21000023232321 its reverse (12323232000012), we get a palindrome (33323255232333).

The spelling of 21000023232321 in words is "twenty-one trillion, twenty-three million, two hundred thirty-two thousand, three hundred twenty-one".