11212021221 has 16 divisors (see below), whose sum is σ = 15291300864. Its totient is φ = 7304208624.

The previous prime is 11212021217. The next prime is 11212021231. The reversal of 11212021221 is 12212021211.

It is not a de Polignac number, because 11212021221 - 2² = 11212021217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11212021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11212021231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28830 + ... + 152496.

It is an arithmetic number, because the mean of its divisors is an integer number (955706304).

Almost surely, 2^11212021221 is an apocalyptic number.

It is an amenable number.

11212021221 is a deficient number, since it is larger than the sum of its proper divisors (4079279643).

11212021221 is a wasteful number, since it uses less digits than its factorization.

11212021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124360.

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

Adding to 11212021221 its reverse (12212021211), we get a palindrome (23424042432).

The spelling of 11212021221 in words is "eleven billion, two hundred twelve million, twenty-one thousand, two hundred twenty-one".