21111122012 has 6 divisors (see below), whose sum is σ = 36944463528. Its totient is φ = 10555561004.

The previous prime is 21111122003. The next prime is 21111122093. The reversal of 21111122012 is 21022111112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2638890248 + ... + 2638890255.

It is an arithmetic number, because the mean of its divisors is an integer number (6157410588).

Almost surely, 2^21111122012 is an apocalyptic number.

It is an amenable number.

21111122012 is a deficient number, since it is larger than the sum of its proper divisors (15833341516).

21111122012 is a wasteful number, since it uses less digits than its factorization.

21111122012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5277780507 (or 5277780505 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21111122012 its reverse (21022111112), we get a palindrome (42133233124).

The spelling of 21111122012 in words is "twenty-one billion, one hundred eleven million, one hundred twenty-two thousand, twelve".