10001221001 has 2 divisors, whose sum is σ = 10001221002. Its totient is φ = 10001221000.

The previous prime is 10001220947. The next prime is 10001221003. The reversal of 10001221001 is 10012210001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6715638601 + 3285582400 = 81949^2 + 57320^2 .

It is a cyclic number.

It is not a de Polignac number, because 10001221001 - 2⁶ = 10001220937 is a prime.

Together with 10001221003, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 10001221001.

It is not a weakly prime, because it can be changed into another prime (10001221003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5000610500 + 5000610501.

It is an arithmetic number, because the mean of its divisors is an integer number (5000610501).

Almost surely, 2^10001221001 is an apocalyptic number.

It is an amenable number.

10001221001 is a deficient number, since it is larger than the sum of its proper divisors (1).

10001221001 is an equidigital number, since it uses as much as digits as its factorization.

10001221001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 10001221001 its reverse (10012210001), we get a palindrome (20013431002).

The spelling of 10001221001 in words is "ten billion, one million, two hundred twenty-one thousand, one".