21001110012 has 72 divisors (see below), whose sum is σ = 54103169120. Its totient is φ = 6866881920.

The previous prime is 21001109999. The next prime is 21001110103.

It is a happy number.

21001110012 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×21001110012² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 21001109976 and 21001110003.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 806289 + ... + 831927.

Almost surely, 2^21001110012 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21001110012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27051584560).

21001110012 is an abundant number, since it is smaller than the sum of its proper divisors (33102059108).

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

21001110012 is a wasteful number, since it uses less digits than its factorization.

21001110012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26083 (or 26078 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The spelling of 21001110012 in words is "twenty-one billion, one million, one hundred ten thousand, twelve".