2001221201 has 6 divisors (see below), whose sum is σ = 2327951250. Its totient is φ = 1715332416.

The previous prime is 2001221141. The next prime is 2001221203. The reversal of 2001221201 is 1021221002.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1027843600 + 973377601 = 32060^2 + 31199^2 .

It is not a de Polignac number, because 2001221201 - 2¹⁴ = 2001204817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2001221203) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 20420576 + ... + 20420673.

It is an arithmetic number, because the mean of its divisors is an integer number (387991875).

Almost surely, 2^2001221201 is an apocalyptic number.

It is an amenable number.

2001221201 is a deficient number, since it is larger than the sum of its proper divisors (326730049).

2001221201 is an equidigital number, since it uses as much as digits as its factorization.

2001221201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40841263 (or 40841256 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 2001221201 is about 44735.0109086831. The cubic root of 2001221201 is about 1260.1774338602.

Adding to 2001221201 its reverse (1021221002), we get a palindrome (3022442203).

The spelling of 2001221201 in words is "two billion, one million, two hundred twenty-one thousand, two hundred one".