21121211210012 has 12 divisors (see below), whose sum is σ = 36963812252640. Its totient is φ = 10560121994976.

The previous prime is 21121211209963. The next prime is 21121211210017. The reversal of 21121211210012 is 21001211212112.

It is a super-2 number, since 2×21121211210012² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121211210017) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120804233 + ... + 120978944.

It is an arithmetic number, because the mean of its divisors is an integer number (3080317687720).

Almost surely, 2^{21121211210012} is an apocalyptic number.

It is an amenable number.

21121211210012 is a deficient number, since it is larger than the sum of its proper divisors (15842601042628).

21121211210012 is a wasteful number, since it uses less digits than its factorization.

21121211210012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241805020 (or 241805018 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21121211210012 its reverse (21001211212112), we get a palindrome (42122422422124).

The spelling of 21121211210012 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred eleven million, two hundred ten thousand, twelve".