221121000021001 has 2 divisors, whose sum is σ = 221121000021002. Its totient is φ = 221121000021000.

The previous prime is 221121000020993. The next prime is 221121000021011. The reversal of 221121000021001 is 100120000121122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 143192359622601 + 77928640398400 = 11966301^2 + 8827720^2 .

It is a cyclic number.

It is not a de Polignac number, because 221121000021001 - 2³ = 221121000020993 is a prime.

It is not a weakly prime, because it can be changed into another prime (221121000021011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110560500010500 + 110560500010501.

It is an arithmetic number, because the mean of its divisors is an integer number (110560500010501).

Almost surely, 2^{221121000021001} is an apocalyptic number.

It is an amenable number.

221121000021001 is a deficient number, since it is larger than the sum of its proper divisors (1).

221121000021001 is an equidigital number, since it uses as much as digits as its factorization.

221121000021001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 221121000021001 its reverse (100120000121122), we get a palindrome (321241000142123).

The spelling of 221121000021001 in words is "two hundred twenty-one trillion, one hundred twenty-one billion, twenty-one thousand, one".