21221220220011 has 144 divisors (see below), whose sum is σ = 37968317861760. Its totient is φ = 11355972526080.

The previous prime is 21221220219967. The next prime is 21221220220019. The reversal of 21221220220011 is 11002202212212.

It is a happy number.

21221220220011 is a `hidden beast` number, since 2 + 1 + 221 + 220 + 220 + 0 + 1 + 1 = 666.

It is not a de Polignac number, because 21221220220011 - 2¹⁸ = 21221219957867 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21221220220019) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 282058180 + ... + 282133406.

It is an arithmetic number, because the mean of its divisors is an integer number (263668874040).

Almost surely, 2^{21221220220011} is an apocalyptic number.

21221220220011 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21221220220011 is a deficient number, since it is larger than the sum of its proper divisors (16747097641749).

21221220220011 is a wasteful number, since it uses less digits than its factorization.

21221220220011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75654 (or 75644 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21221220220011 its reverse (11002202212212), we get a palindrome (32223422432223).

The spelling of 21221220220011 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twenty million, two hundred twenty thousand, eleven".