21111103212 has 12 divisors (see below), whose sum is σ = 49259240856. Its totient is φ = 7037034400.

The previous prime is 21111103177. The next prime is 21111103241. The reversal of 21111103212 is 21230111112.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-3 number, since 3×21111103212³ (a number of 32 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21111103191 and 21111103200.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 879629289 + ... + 879629312.

It is an arithmetic number, because the mean of its divisors is an integer number (4104936738).

Almost surely, 2^21111103212 is an apocalyptic number.

It is an amenable number.

21111103212 is an abundant number, since it is smaller than the sum of its proper divisors (28148137644).

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

21111103212 is a wasteful number, since it uses less digits than its factorization.

21111103212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1759258608 (or 1759258606 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 21111103212 its reverse (21230111112), we get a palindrome (42341214324).

The spelling of 21111103212 in words is "twenty-one billion, one hundred eleven million, one hundred three thousand, two hundred twelve".