2001002002001 has 2 divisors, whose sum is σ = 2001002002002. Its totient is φ = 2001002002000.

The previous prime is 2001002001961. The next prime is 2001002002003. The reversal of 2001002002001 is 1002002001002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1900471787776 + 100530214225 = 1378576^2 + 317065^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001002002001 - 2¹⁴ = 2001001985617 is a prime.

Together with 2001002002003, 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 2001002002001.

It is not a weakly prime, because it can be changed into another prime (2001002002003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000501001000 + 1000501001001.

It is an arithmetic number, because the mean of its divisors is an integer number (1000501001001).

Almost surely, 2^{2001002002001} is an apocalyptic number.

It is an amenable number.

2001002002001 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001002002001 is an equidigital number, since it uses as much as digits as its factorization.

2001002002001 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 8.

Adding to 2001002002001 its reverse (1002002001002), we get a palindrome (3003004003003).

Subtracting from 2001002002001 its reverse (1002002001002), we obtain a palindrome (999000000999).

The spelling of 2001002002001 in words is "two trillion, one billion, two million, two thousand, one".