221021111220001 has 2 divisors, whose sum is σ = 221021111220002. Its totient is φ = 221021111220000.

The previous prime is 221021111219999. The next prime is 221021111220011. The reversal of 221021111220001 is 100022111120122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 206263597134400 + 14757514085601 = 14361880^2 + 3841551^2 .

It is a cyclic number.

It is not a de Polignac number, because 221021111220001 - 2¹ = 221021111219999 is a prime.

Together with 221021111219999, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (221021111220011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110510555610000 + 110510555610001.

It is an arithmetic number, because the mean of its divisors is an integer number (110510555610001).

Almost surely, 2^{221021111220001} is an apocalyptic number.

It is an amenable number.

221021111220001 is a deficient number, since it is larger than the sum of its proper divisors (1).

221021111220001 is an equidigital number, since it uses as much as digits as its factorization.

221021111220001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 221021111220001 its reverse (100022111120122), we get a palindrome (321043222340123).

The spelling of 221021111220001 in words is "two hundred twenty-one trillion, twenty-one billion, one hundred eleven million, two hundred twenty thousand, one".