21212111210 has 32 divisors (see below), whose sum is σ = 38769736320. Its totient is φ = 8355143872.

The previous prime is 21212111209. The next prime is 21212111213. The reversal of 21212111210 is 1211121212.

It is not an unprimeable number, because it can be changed into a prime (21212111213) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 119336 + ... + 238044.

It is an arithmetic number, because the mean of its divisors is an integer number (1211554260).

Almost surely, 2^21212111210 is an apocalyptic number.

21212111210 is a deficient number, since it is larger than the sum of its proper divisors (17557625110).

21212111210 is a wasteful number, since it uses less digits than its factorization.

21212111210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118990.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21212111210 its reverse (1211121212), we get a palindrome (22423232422).

The spelling of 21212111210 in words is "twenty-one billion, two hundred twelve million, one hundred eleven thousand, two hundred ten".