21210010101211 has 4 divisors (see below), whose sum is σ = 21277773712072. Its totient is φ = 21142246490352.

The previous prime is 21210010101209. The next prime is 21210010101233. The reversal of 21210010101211 is 11210101001212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21210010101211 - 2¹ = 21210010101209 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21210010101191 and 21210010101200.

It is not an unprimeable number, because it can be changed into a prime (21210010171211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33881804961 + ... + 33881805586.

It is an arithmetic number, because the mean of its divisors is an integer number (5319443428018).

Almost surely, 2^{21210010101211} is an apocalyptic number.

21210010101211 is a deficient number, since it is larger than the sum of its proper divisors (67763610861).

21210010101211 is an equidigital number, since it uses as much as digits as its factorization.

21210010101211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67763610860.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21210010101211 its reverse (11210101001212), we get a palindrome (32420111102423).

Subtracting from 21210010101211 its reverse (11210101001212), we obtain a palindrome (9999909099999).

The spelling of 21210010101211 in words is "twenty-one trillion, two hundred ten billion, ten million, one hundred one thousand, two hundred eleven".