21212212220222 has 16 divisors (see below), whose sum is σ = 31846175207280. Its totient is φ = 10596821854272.

The previous prime is 21212212220209. The next prime is 21212212220237. The reversal of 21212212220222 is 22202221221212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31272908 + ... + 31944000.

It is an arithmetic number, because the mean of its divisors is an integer number (1990385950455).

Almost surely, 2^{21212212220222} is an apocalyptic number.

21212212220222 is a deficient number, since it is larger than the sum of its proper divisors (10633962987058).

21212212220222 is a wasteful number, since it uses less digits than its factorization.

21212212220222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 684907.

The product of its (nonzero) digits is 1024, while the sum is 23.

Adding to 21212212220222 its reverse (22202221221212), we get a palindrome (43414433441434).

The spelling of 21212212220222 in words is "twenty-one trillion, two hundred twelve billion, two hundred twelve million, two hundred twenty thousand, two hundred twenty-two".