11001220021221 has 16 divisors (see below), whose sum is σ = 14718372596928. Its totient is φ = 7309114531200.

The previous prime is 11001220021193. The next prime is 11001220021229. The reversal of 11001220021221 is 12212002210011.

It is not a de Polignac number, because 11001220021221 - 2⁵ = 11001220021189 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11001220021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11001220021229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4983601 + ... + 6843881.

It is an arithmetic number, because the mean of its divisors is an integer number (919898287308).

Almost surely, 2^{11001220021221} is an apocalyptic number.

It is an amenable number.

11001220021221 is a deficient number, since it is larger than the sum of its proper divisors (3717152575707).

11001220021221 is a wasteful number, since it uses less digits than its factorization.

11001220021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1867012.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 11001220021221 its reverse (12212002210011), we get a palindrome (23213222231232).

The spelling of 11001220021221 in words is "eleven trillion, one billion, two hundred twenty million, twenty-one thousand, two hundred twenty-one".