21012222212 has 6 divisors (see below), whose sum is σ = 36771388878. Its totient is φ = 10506111104.

The previous prime is 21012222193. The next prime is 21012222221. The reversal of 21012222212 is 21222221012.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 16696257796 + 4315964416 = 129214^2 + 65696^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2626527773 + ... + 2626527780.

It is an arithmetic number, because the mean of its divisors is an integer number (6128564813).

Almost surely, 2^21012222212 is an apocalyptic number.

It is an amenable number.

21012222212 is a deficient number, since it is larger than the sum of its proper divisors (15759166666).

21012222212 is a wasteful number, since it uses less digits than its factorization.

21012222212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5253055557 (or 5253055555 counting only the distinct ones).

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

Adding to 21012222212 its reverse (21222221012), we get a palindrome (42234443224).

The spelling of 21012222212 in words is "twenty-one billion, twelve million, two hundred twenty-two thousand, two hundred twelve".