21212202211 has 8 divisors (see below), whose sum is σ = 21531341840. Its totient is φ = 20893137408.

The previous prime is 21212202173. The next prime is 21212202227. The reversal of 21212202211 is 11220221212.

It is a happy number.

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 21212202211 - 2²⁷ = 21077984483 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21212202611) 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, 859435 + ... + 883771.

It is an arithmetic number, because the mean of its divisors is an integer number (2691417730).

Almost surely, 2^21212202211 is an apocalyptic number.

21212202211 is a deficient number, since it is larger than the sum of its proper divisors (319139629).

21212202211 is a wasteful number, since it uses less digits than its factorization.

21212202211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37413.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21212202211 its reverse (11220221212), we get a palindrome (32432423423).

The spelling of 21212202211 in words is "twenty-one billion, two hundred twelve million, two hundred two thousand, two hundred eleven".