213444043321 has 2 divisors, whose sum is σ = 213444043322. Its totient is φ = 213444043320.

The previous prime is 213444043313. The next prime is 213444043327. The reversal of 213444043321 is 123340444312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 199684753321 + 13759290000 = 446861^2 + 117300^2 .

It is a cyclic number.

It is not a de Polignac number, because 213444043321 - 2³ = 213444043313 is a prime.

It is not a weakly prime, because it can be changed into another prime (213444043327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106722021660 + 106722021661.

It is an arithmetic number, because the mean of its divisors is an integer number (106722021661).

Almost surely, 2^213444043321 is an apocalyptic number.

It is an amenable number.

213444043321 is a deficient number, since it is larger than the sum of its proper divisors (1).

213444043321 is an equidigital number, since it uses as much as digits as its factorization.

213444043321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27648, while the sum is 31.

Adding to 213444043321 its reverse (123340444312), we get a palindrome (336784487633).

The spelling of 213444043321 in words is "two hundred thirteen billion, four hundred forty-four million, forty-three thousand, three hundred twenty-one".