21212111110 has 8 divisors (see below), whose sum is σ = 38181800016. Its totient is φ = 8484844440.

The previous prime is 21212111101. The next prime is 21212111143. The reversal of 21212111110 is 1111121212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1060605546 + ... + 1060605565.

It is an arithmetic number, because the mean of its divisors is an integer number (4772725002).

Almost surely, 2^21212111110 is an apocalyptic number.

21212111110 is a deficient number, since it is larger than the sum of its proper divisors (16969688906).

21212111110 is a wasteful number, since it uses less digits than its factorization.

21212111110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2121211118.

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

Adding to 21212111110 its reverse (1111121212), we get a palindrome (22323232322).

The spelling of 21212111110 in words is "twenty-one billion, two hundred twelve million, one hundred eleven thousand, one hundred ten".