21210202211 has 4 divisors (see below), whose sum is σ = 23138402424. Its totient is φ = 19282002000.

The previous prime is 21210202193. The next prime is 21210202219. The reversal of 21210202211 is 11220201212.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21210202211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21210202219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 964100090 + ... + 964100111.

It is an arithmetic number, because the mean of its divisors is an integer number (5784600606).

Almost surely, 2^21210202211 is an apocalyptic number.

21210202211 is a deficient number, since it is larger than the sum of its proper divisors (1928200213).

21210202211 is a wasteful number, since it uses less digits than its factorization.

21210202211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1928200212.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21210202211 its reverse (11220201212), we get a palindrome (32430403423).

Subtracting from 21210202211 its reverse (11220201212), we obtain a palindrome (9990000999).

The spelling of 21210202211 in words is "twenty-one billion, two hundred ten million, two hundred two thousand, two hundred eleven".