21211133021 has 8 divisors (see below), whose sum is σ = 23273754840. Its totient is φ = 19210082112.

The previous prime is 21211132997. The next prime is 21211133033. The reversal of 21211133021 is 12033111212.

It can be written as a sum of positive squares in 4 ways, for example, as 6722196121 + 14488936900 = 81989^2 + 120370^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21211133021 - 2¹⁴ = 21211116637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211133221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15392006 + ... + 15393383.

It is an arithmetic number, because the mean of its divisors is an integer number (2909219355).

Almost surely, 2^21211133021 is an apocalyptic number.

It is an amenable number.

21211133021 is a deficient number, since it is larger than the sum of its proper divisors (2062621819).

21211133021 is a wasteful number, since it uses less digits than its factorization.

21211133021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30785455.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21211133021 its reverse (12033111212), we get a palindrome (33244244233).

The spelling of 21211133021 in words is "twenty-one billion, two hundred eleven million, one hundred thirty-three thousand, twenty-one".