21001111012 has 12 divisors (see below), whose sum is σ = 42002222080. Its totient is φ = 9000476136.

The previous prime is 21001110967. The next prime is 21001111063. The reversal of 21001111012 is 21011110012.

21001111012 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 21001111012.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 375019812 + ... + 375019867.

Almost surely, 2^21001111012 is an apocalyptic number.

It is an amenable number.

21001111012 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21001111012 is a wasteful number, since it uses less digits than its factorization.

21001111012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 750039690 (or 750039688 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21001111012 its reverse (21011110012), we get a palindrome (42012221024).

The spelling of 21001111012 in words is "twenty-one billion, one million, one hundred eleven thousand, twelve".