21321212011 has 8 divisors (see below), whose sum is σ = 23287639104. Its totient is φ = 19359474120.

The previous prime is 21321211979. The next prime is 21321212027. The reversal of 21321212011 is 11021212312.

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 21321212011 - 2⁵ = 21321211979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21321212071) 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, 1162785 + ... + 1180978.

It is an arithmetic number, because the mean of its divisors is an integer number (2910954888).

Almost surely, 2^21321212011 is an apocalyptic number.

21321212011 is a deficient number, since it is larger than the sum of its proper divisors (1966427093).

21321212011 is a wasteful number, since it uses less digits than its factorization.

21321212011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2344601.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21321212011 its reverse (11021212312), we get a palindrome (32342424323).

It can be divided in two parts, 21321 and 212011, that added together give a palindrome (233332).

The spelling of 21321212011 in words is "twenty-one billion, three hundred twenty-one million, two hundred twelve thousand, eleven".