21000112321 has 2 divisors, whose sum is σ = 21000112322. Its totient is φ = 21000112320.

The previous prime is 21000112297. The next prime is 21000112327. The reversal of 21000112321 is 12321100012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20992822321 + 7290000 = 144889^2 + 2700^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000112321 - 2¹³ = 21000104129 is a prime.

It is not a weakly prime, because it can be changed into another prime (21000112327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500056160 + 10500056161.

It is an arithmetic number, because the mean of its divisors is an integer number (10500056161).

Almost surely, 2^21000112321 is an apocalyptic number.

It is an amenable number.

21000112321 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000112321 is an equidigital number, since it uses as much as digits as its factorization.

21000112321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21000112321 its reverse (12321100012), we get a palindrome (33321212333).

The spelling of 21000112321 in words is "twenty-one billion, one hundred twelve thousand, three hundred twenty-one".