21012222122 has 32 divisors (see below), whose sum is σ = 34110901440. Its totient is φ = 9670984960.

The previous prime is 21012222109. The next prime is 21012222157. The reversal of 21012222122 is 22122221012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a self number, because there is not a number n which added to its sum of digits gives 21012222122.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 368597 + ... + 421767.

It is an arithmetic number, because the mean of its divisors is an integer number (1065965670).

Almost surely, 2^21012222122 is an apocalyptic number.

21012222122 is a deficient number, since it is larger than the sum of its proper divisors (13098679318).

21012222122 is a wasteful number, since it uses less digits than its factorization.

21012222122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53446.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21012222122 its reverse (22122221012), we get a palindrome (43134443134).

The spelling of 21012222122 in words is "twenty-one billion, twelve million, two hundred twenty-two thousand, one hundred twenty-two".