221042042321 has 2 divisors, whose sum is σ = 221042042322. Its totient is φ = 221042042320.

The previous prime is 221042042303. The next prime is 221042042323. The reversal of 221042042321 is 123240240122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 165678305296 + 55363737025 = 407036^2 + 235295^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221042042321 is a prime.

Together with 221042042323, 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 (221042042323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110521021160 + 110521021161.

It is an arithmetic number, because the mean of its divisors is an integer number (110521021161).

Almost surely, 2^221042042321 is an apocalyptic number.

It is an amenable number.

221042042321 is a deficient number, since it is larger than the sum of its proper divisors (1).

221042042321 is an equidigital number, since it uses as much as digits as its factorization.

221042042321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1536, while the sum is 23.

Adding to 221042042321 its reverse (123240240122), we get a palindrome (344282282443).

The spelling of 221042042321 in words is "two hundred twenty-one billion, forty-two million, forty-two thousand, three hundred twenty-one".