21121211100012 has 24 divisors (see below), whose sum is σ = 49318053120000. Its totient is φ = 7035371240016.

The previous prime is 21121211100007. The next prime is 21121211100061. The reversal of 21121211100012 is 21000111212112.

It is a happy number.

It is a super-2 number, since 2×21121211100012² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21121211099964 and 21121211100000.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 629040012 + ... + 629073587.

It is an arithmetic number, because the mean of its divisors is an integer number (2054918880000).

Almost surely, 2^{21121211100012} is an apocalyptic number.

It is an amenable number.

21121211100012 is an abundant number, since it is smaller than the sum of its proper divisors (28196842019988).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21121211100012 is a wasteful number, since it uses less digits than its factorization.

21121211100012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1258115005 (or 1258115003 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21121211100012 its reverse (21000111212112), we get a palindrome (42121322312124).

The spelling of 21121211100012 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred eleven million, one hundred thousand, twelve".