21221222000212 has 18 divisors (see below), whose sum is σ = 40213587844878. Its totient is φ = 9794410153632.

The previous prime is 21221222000179. The next prime is 21221222000221. The reversal of 21221222000212 is 21200022212212.

It can be written as a sum of positive squares in 3 ways, for example, as 2854734643216 + 18366487356996 = 1689596^2 + 4285614^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21221222000212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 15696169443 + ... + 15696170794.

Almost surely, 2^{21221222000212} is an apocalyptic number.

It is an amenable number.

21221222000212 is a deficient number, since it is larger than the sum of its proper divisors (18992365844666).

21221222000212 is a wasteful number, since it uses less digits than its factorization.

21221222000212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31392340267 (or 31392340252 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 21221222000212 its reverse (21200022212212), we get a palindrome (42421244212424).

The spelling of 21221222000212 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twenty-two million, two hundred twelve", and thus it is an aban number.