21001211222222 has 32 divisors (see below), whose sum is σ = 40629302507520. Its totient is φ = 7900142150880.

The previous prime is 21001211222219. The next prime is 21001211222249. The reversal of 21001211222222 is 22222211210012.

It is a junction number, because it is equal to n+sod(n) for n = 21001211222194 and 21001211222203.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2351228318 + ... + 2351237249.

It is an arithmetic number, because the mean of its divisors is an integer number (1269665703360).

Almost surely, 2^{21001211222222} is an apocalyptic number.

21001211222222 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21001211222222 is a deficient number, since it is larger than the sum of its proper divisors (19628091285298).

21001211222222 is a wasteful number, since it uses less digits than its factorization.

21001211222222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4702465616.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 21001211222222 its reverse (22222211210012), we get a palindrome (43223422432234).

The spelling of 21001211222222 in words is "twenty-one trillion, one billion, two hundred eleven million, two hundred twenty-two thousand, two hundred twenty-two".