2001222001 has 2 divisors, whose sum is σ = 2001222002. Its totient is φ = 2001222000.

The previous prime is 2001221983. The next prime is 2001222011. The reversal of 2001222001 is 1002221002.

It is an a-pointer prime, because the next prime (2001222011) can be obtained adding 2001222001 to its sum of digits (10).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1475712225 + 525509776 = 38415^2 + 22924^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001222001 - 2¹⁷ = 2001090929 is a prime.

It is not a weakly prime, because it can be changed into another prime (2001222011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000611000 + 1000611001.

It is an arithmetic number, because the mean of its divisors is an integer number (1000611001).

Almost surely, 2^2001222001 is an apocalyptic number.

It is an amenable number.

2001222001 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001222001 is an equidigital number, since it uses as much as digits as its factorization.

2001222001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 2001222001 is about 44735.0198502247. The cubic root of 2001222001 is about 1260.1776017813.

Adding to 2001222001 its reverse (1002221002), we get a palindrome (3003443003).

Subtracting from 2001222001 its reverse (1002221002), we obtain a palindrome (999000999).

The spelling of 2001222001 in words is "two billion, one million, two hundred twenty-two thousand, one".