21212112110 has 32 divisors (see below), whose sum is σ = 43689101760. Its totient is φ = 7263931392.

The previous prime is 21212112109. The next prime is 21212112113. The reversal of 21212112110 is 1121121212.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212112113) 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, 124739 + ... + 240798.

It is an arithmetic number, because the mean of its divisors is an integer number (1365284430).

Almost surely, 2^21212112110 is an apocalyptic number.

21212112110 is an abundant number, since it is smaller than the sum of its proper divisors (22476989650).

21212112110 is a wasteful number, since it uses less digits than its factorization.

21212112110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366380.

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

Adding to 21212112110 its reverse (1121121212), we get a palindrome (22333233322).

The spelling of 21212112110 in words is "twenty-one billion, two hundred twelve million, one hundred twelve thousand, one hundred ten".