1001222220221 has 4 divisors (see below), whose sum is σ = 1001224224000. Its totient is φ = 1001220216444.

The previous prime is 1001222220161. The next prime is 1001222220241. The reversal of 1001222220221 is 1220222221001.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1001222220221 - 2¹⁴ = 1001222203837 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1001222220221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001222220241) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 425060 + ... + 1477538.

It is an arithmetic number, because the mean of its divisors is an integer number (250306056000).

Almost surely, 2^{1001222220221} is an apocalyptic number.

It is an amenable number.

1001222220221 is a deficient number, since it is larger than the sum of its proper divisors (2003779).

1001222220221 is an equidigital number, since it uses as much as digits as its factorization.

1001222220221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2003778.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 1001222220221 its reverse (1220222221001), we get a palindrome (2221444441222).

The spelling of 1001222220221 in words is "one trillion, one billion, two hundred twenty-two million, two hundred twenty thousand, two hundred twenty-one".