21212121202012 has 12 divisors (see below), whose sum is σ = 39976689957736. Its totient is φ = 9790209785520.

The previous prime is 21212121202003. The next prime is 21212121202031. The reversal of 21212121202012 is 21020212121212.

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, 203962703814 + ... + 203962703917.

Almost surely, 2^{21212121202012} is an apocalyptic number.

It is an amenable number.

21212121202012 is a deficient number, since it is larger than the sum of its proper divisors (18764568755724).

21212121202012 is a wasteful number, since it uses less digits than its factorization.

21212121202012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407925407748 (or 407925407746 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21212121202012 its reverse (21020212121212), we get a palindrome (42232333323224).

The spelling of 21212121202012 in words is "twenty-one trillion, two hundred twelve billion, one hundred twenty-one million, two hundred two thousand, twelve".