21212000006 has 4 divisors (see below), whose sum is σ = 31818000012. Its totient is φ = 10606000002.

The previous prime is 21211999979. The next prime is 21212000021. The reversal of 21212000006 is 60000021212.

It is a semiprime because it is the product of two primes.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5303000000 + ... + 5303000003.

It is an arithmetic number, because the mean of its divisors is an integer number (7954500003).

Almost surely, 2^21212000006 is an apocalyptic number.

21212000006 is a deficient number, since it is larger than the sum of its proper divisors (10606000006).

21212000006 is a wasteful number, since it uses less digits than its factorization.

21212000006 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10606000005.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21212000006 its reverse (60000021212), we get a palindrome (81212021218).

The spelling of 21212000006 in words is "twenty-one billion, two hundred twelve million, six", and thus it is an aban number.