21012001222 has 8 divisors (see below), whose sum is σ = 31589149896. Its totient is φ = 10482284592.

The previous prime is 21012001217. The next prime is 21012001237. The reversal of 21012001222 is 22210021012.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11856903 + ... + 11858674.

It is an arithmetic number, because the mean of its divisors is an integer number (3948643737).

Almost surely, 2^21012001222 is an apocalyptic number.

21012001222 is a deficient number, since it is larger than the sum of its proper divisors (10577148674).

21012001222 is a wasteful number, since it uses less digits than its factorization.

21012001222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23716022.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21012001222 its reverse (22210021012), we get a palindrome (43222022234).

The spelling of 21012001222 in words is "twenty-one billion, twelve million, one thousand, two hundred twenty-two".