21221121211011 has 48 divisors (see below), whose sum is σ = 34143113571840. Its totient is φ = 12639517672320.

The previous prime is 21221121211007. The next prime is 21221121211097. The reversal of 21221121211011 is 11011212112212.

It is a happy number.

21221121211011 is a `hidden beast` number, since 212 + 211 + 21 + 211 + 0 + 11 = 666.

It is not a de Polignac number, because 21221121211011 - 2² = 21221121211007 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21221121211811) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 37718346 + ... + 38276831.

It is an arithmetic number, because the mean of its divisors is an integer number (711314866080).

Almost surely, 2^{21221121211011} is an apocalyptic number.

21221121211011 is a deficient number, since it is larger than the sum of its proper divisors (12921992360829).

21221121211011 is a wasteful number, since it uses less digits than its factorization.

21221121211011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75995296 (or 75995293 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 18.

Adding to 21221121211011 its reverse (11011212112212), we get a palindrome (32232333323223).

The spelling of 21221121211011 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred twenty-one million, two hundred eleven thousand, eleven".