21212131109 has 8 divisors (see below), whose sum is σ = 22874755680. Its totient is φ = 19553924016.

The previous prime is 21212131093. The next prime is 21212131111. The reversal of 21212131109 is 90113121212.

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 21212131109 - 2⁴ = 21212131093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212133109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1094387 + ... + 1113600.

It is an arithmetic number, because the mean of its divisors is an integer number (2859344460).

Almost surely, 2^21212131109 is an apocalyptic number.

It is an amenable number.

21212131109 is a deficient number, since it is larger than the sum of its proper divisors (1662624571).

21212131109 is a wasteful number, since it uses less digits than its factorization.

21212131109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2208739.

The product of its (nonzero) digits is 216, while the sum is 23.

The spelling of 21212131109 in words is "twenty-one billion, two hundred twelve million, one hundred thirty-one thousand, one hundred nine".