21021102211 has 8 divisors (see below), whose sum is σ = 21056162400. Its totient is φ = 20986067520.

The previous prime is 21021102209. The next prime is 21021102283. The reversal of 21021102211 is 11220112012.

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

It is a cyclic number.

It is not a de Polignac number, because 21021102211 - 2¹ = 21021102209 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21021102191 and 21021102200.

It is not an unprimeable number, because it can be changed into a prime (21021100211) 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, 2285041 + ... + 2294221.

It is an arithmetic number, because the mean of its divisors is an integer number (2632020300).

Almost surely, 2^21021102211 is an apocalyptic number.

21021102211 is a deficient number, since it is larger than the sum of its proper divisors (35060189).

21021102211 is an equidigital number, since it uses as much as digits as its factorization.

21021102211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12749.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21021102211 its reverse (11220112012), we get a palindrome (32241214223).

The spelling of 21021102211 in words is "twenty-one billion, twenty-one million, one hundred two thousand, two hundred eleven".