21003630012 has 72 divisors (see below), whose sum is σ = 56286502272. Its totient is φ = 6592233600.

The previous prime is 21003629963. The next prime is 21003630013.

21003630012 is a `hidden beast` number, since 21 + 0 + 0 + 3 + 630 + 0 + 12 = 666.

21003630012 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21003630013) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 213039 + ... + 295622.

It is an arithmetic number, because the mean of its divisors is an integer number (781756976).

Almost surely, 2^21003630012 is an apocalyptic number.

It is an amenable number.

21003630012 is an abundant number, since it is smaller than the sum of its proper divisors (35282872260).

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

21003630012 is a wasteful number, since it uses less digits than its factorization.

21003630012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 508739 (or 508734 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The spelling of 21003630012 in words is "twenty-one billion, three million, six hundred thirty thousand, twelve".