21212022004 has 12 divisors (see below), whose sum is σ = 38124310084. Its totient is φ = 10319361984.

The previous prime is 21212021959. The next prime is 21212022019. The reversal of 21212022004 is 40022021212.

It can be written as a sum of positive squares in 2 ways, for example, as 9476633104 + 11735388900 = 97348^2 + 108330^2 .

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 in 3 ways as a sum of consecutive naturals, for example, 71662089 + ... + 71662384.

Almost surely, 2^21212022004 is an apocalyptic number.

It is an amenable number.

21212022004 is a deficient number, since it is larger than the sum of its proper divisors (16912288080).

21212022004 is a wasteful number, since it uses less digits than its factorization.

21212022004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143324514 (or 143324512 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 21212022004 its reverse (40022021212), we get a palindrome (61234043216).

The spelling of 21212022004 in words is "twenty-one billion, two hundred twelve million, twenty-two thousand, four".