21100211212 has 6 divisors (see below), whose sum is σ = 36925369628. Its totient is φ = 10550105604.

The previous prime is 21100211191. The next prime is 21100211219. The reversal of 21100211212 is 21211200112.

It is a junction number, because it is equal to n+sod(n) for n = 21100211192 and 21100211201.

It is not an unprimeable number, because it can be changed into a prime (21100211219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2637526398 + ... + 2637526405.

Almost surely, 2^21100211212 is an apocalyptic number.

It is an amenable number.

21100211212 is a deficient number, since it is larger than the sum of its proper divisors (15825158416).

21100211212 is a wasteful number, since it uses less digits than its factorization.

21100211212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5275052807 (or 5275052805 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21100211212 its reverse (21211200112), we get a palindrome (42311411324).

The spelling of 21100211212 in words is "twenty-one billion, one hundred million, two hundred eleven thousand, two hundred twelve".