1001221210001 has 2 divisors, whose sum is σ = 1001221210002. Its totient is φ = 1001221210000.

The previous prime is 1001221209971. The next prime is 1001221210007. The reversal of 1001221210001 is 1000121221001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 967372569601 + 33848640400 = 983551^2 + 183980^2 .

It is a cyclic number.

It is not a de Polignac number, because 1001221210001 - 2²⁶ = 1001154101137 is a prime.

It is a super-2 number, since 2×1001221210001² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1001221210007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500610605000 + 500610605001.

It is an arithmetic number, because the mean of its divisors is an integer number (500610605001).

Almost surely, 2^{1001221210001} is an apocalyptic number.

It is an amenable number.

1001221210001 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001221210001 is an equidigital number, since it uses as much as digits as its factorization.

1001221210001 is an evil number, because the sum of its binary digits is even.

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

Adding to 1001221210001 its reverse (1000121221001), we get a palindrome (2001342431002).

The spelling of 1001221210001 in words is "one trillion, one billion, two hundred twenty-one million, two hundred ten thousand, one".