21000212222 has 16 divisors (see below), whose sum is σ = 35095133952. Its totient is φ = 9342453720.

The previous prime is 21000212143. The next prime is 21000212239. The reversal of 21000212222 is 22221200012.

It is a junction number, because it is equal to n+sod(n) for n = 21000212197 and 21000212206.

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 7 ways as a sum of consecutive naturals, for example, 10153808 + ... + 10155875.

It is an arithmetic number, because the mean of its divisors is an integer number (2193445872).

Almost surely, 2^21000212222 is an apocalyptic number.

21000212222 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21000212222 is a deficient number, since it is larger than the sum of its proper divisors (14094921730).

21000212222 is a wasteful number, since it uses less digits than its factorization.

21000212222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20309743.

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 21000212222 its reverse (22221200012), we get a palindrome (43221412234).

The spelling of 21000212222 in words is "twenty-one billion, two hundred twelve thousand, two hundred twenty-two".