2001222021 has 8 divisors (see below), whose sum is σ = 2730349600. Its totient is φ = 1303121232.

The previous prime is 2001222011. The next prime is 2001222023. The reversal of 2001222021 is 1202221002.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-2001222021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001221988 and 2001222006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001222023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7756546 + ... + 7756803.

It is an arithmetic number, because the mean of its divisors is an integer number (341293700).

Almost surely, 2^2001222021 is an apocalyptic number.

It is an amenable number.

2001222021 is a deficient number, since it is larger than the sum of its proper divisors (729127579).

2001222021 is a wasteful number, since it uses less digits than its factorization.

2001222021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15513395.

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 2001222021 is about 44735.0200737632. The cubic root of 2001222021 is about 1260.1776059794.

Adding to 2001222021 its reverse (1202221002), we get a palindrome (3203443023).

It can be divided in two parts, 200 and 1222021, that added together give a palindrome (1222221).

The spelling of 2001222021 in words is "two billion, one million, two hundred twenty-two thousand, twenty-one".