21312244001 has 2 divisors, whose sum is σ = 21312244002. Its totient is φ = 21312244000.

The previous prime is 21312243961. The next prime is 21312244003. The reversal of 21312244001 is 10044221312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21243354001 + 68890000 = 145751^2 + 8300^2 .

It is a cyclic number.

It is not a de Polignac number, because 21312244001 - 2¹⁰ = 21312242977 is a prime.

Together with 21312244003, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21312244003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10656122000 + 10656122001.

It is an arithmetic number, because the mean of its divisors is an integer number (10656122001).

Almost surely, 2^21312244001 is an apocalyptic number.

It is an amenable number.

21312244001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21312244001 is an equidigital number, since it uses as much as digits as its factorization.

21312244001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21312244001 its reverse (10044221312), we get a palindrome (31356465313).

The spelling of 21312244001 in words is "twenty-one billion, three hundred twelve million, two hundred forty-four thousand, one".