21221122011021 has 24 divisors (see below), whose sum is σ = 31071303446040. Its totient is φ = 13955269200000.

The previous prime is 21221122011007. The next prime is 21221122011041. The reversal of 21221122011021 is 12011022112212.

21221122011021 is a `hidden beast` number, since 212 + 211 + 220 + 1 + 1 + 0 + 21 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2715208588521 + 18505913422500 = 1647789^2 + 4301850^2 .

It is not a de Polignac number, because 21221122011021 - 2⁹ = 21221122010509 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21221122010985 and 21221122011003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221122011041) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43148730 + ... + 43637771.

It is an arithmetic number, because the mean of its divisors is an integer number (1294637643585).

Almost surely, 2^{21221122011021} is an apocalyptic number.

It is an amenable number.

21221122011021 is a deficient number, since it is larger than the sum of its proper divisors (9850181435019).

21221122011021 is a wasteful number, since it uses less digits than its factorization.

21221122011021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86786877 (or 86786874 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21221122011021 its reverse (12011022112212), we get a palindrome (33232144123233).

The spelling of 21221122011021 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred twenty-two million, eleven thousand, twenty-one".