1220211001001 has 2 divisors, whose sum is σ = 1220211001002. Its totient is φ = 1220211001000.

The previous prime is 1220211000997. The next prime is 1220211001021. The reversal of 1220211001001 is 1001001120221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 832765753600 + 387445247401 = 912560^2 + 622451^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220211001001 - 2² = 1220211000997 is a prime.

It is not a weakly prime, because it can be changed into another prime (1220211001021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610105500500 + 610105500501.

It is an arithmetic number, because the mean of its divisors is an integer number (610105500501).

Almost surely, 2^{1220211001001} is an apocalyptic number.

It is an amenable number.

1220211001001 is a deficient number, since it is larger than the sum of its proper divisors (1).

1220211001001 is an equidigital number, since it uses as much as digits as its factorization.

1220211001001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 1220211001001 its reverse (1001001120221), we get a palindrome (2221212121222).

The spelling of 1220211001001 in words is "one trillion, two hundred twenty billion, two hundred eleven million, one thousand, one".