21232212021 has 32 divisors (see below), whose sum is σ = 31820572800. Its totient is φ = 13990838400.

The previous prime is 21232212011. The next prime is 21232212041. The reversal of 21232212021 is 12021223212.

It is not a de Polignac number, because 21232212021 - 2¹⁴ = 21232195637 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21232211985 and 21232212003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21232212011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1676250 + ... + 1688868.

It is an arithmetic number, because the mean of its divisors is an integer number (994392900).

Almost surely, 2^21232212021 is an apocalyptic number.

It is an amenable number.

21232212021 is a deficient number, since it is larger than the sum of its proper divisors (10588360779).

21232212021 is a wasteful number, since it uses less digits than its factorization.

21232212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13346 (or 13340 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21232212021 its reverse (12021223212), we get a palindrome (33253435233).

It can be divided in two parts, 2123 and 2212021, that added together give a square (2214144 = 1488²).

The spelling of 21232212021 in words is "twenty-one billion, two hundred thirty-two million, two hundred twelve thousand, twenty-one".