21021211222 has 24 divisors (see below), whose sum is σ = 36304084872. Its totient is φ = 9052192800.

The previous prime is 21021211219. The next prime is 21021211247. The reversal of 21021211222 is 22211212012.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21021211196 and 21021211205.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1315479 + ... + 1331362.

It is an arithmetic number, because the mean of its divisors is an integer number (1512670203).

Almost surely, 2^21021211222 is an apocalyptic number.

21021211222 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21021211222 is a deficient number, since it is larger than the sum of its proper divisors (15282873650).

21021211222 is a wasteful number, since it uses less digits than its factorization.

21021211222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2646892 (or 2646873 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21021211222 its reverse (22211212012), we get a palindrome (43232423234).

The spelling of 21021211222 in words is "twenty-one billion, twenty-one million, two hundred eleven thousand, two hundred twenty-two".