21212022006 has 24 divisors (see below), whose sum is σ = 52525007184. Its totient is φ = 6060577680.

The previous prime is 21212021959. The next prime is 21212022019. The reversal of 21212022006 is 60022021212.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a self number, because there is not a number n which added to its sum of digits gives 21212022006.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 84174565 + ... + 84174816.

It is an arithmetic number, because the mean of its divisors is an integer number (2188541966).

Almost surely, 2^21212022006 is an apocalyptic number.

21212022006 is an abundant number, since it is smaller than the sum of its proper divisors (31312985178).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21212022006 is a wasteful number, since it uses less digits than its factorization.

21212022006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168349396 (or 168349393 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21212022006 its reverse (60022021212), we get a palindrome (81234043218).

The spelling of 21212022006 in words is "twenty-one billion, two hundred twelve million, twenty-two thousand, six".