21003003312 has 20 divisors (see below), whose sum is σ = 54257758680. Its totient is φ = 7001001088.

The previous prime is 21003003283. The next prime is 21003003323. The reversal of 21003003312 is 21330030012.

It is a super-2 number, since 2×21003003312² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21003003291 and 21003003300.

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, 218781237 + ... + 218781332.

It is an arithmetic number, because the mean of its divisors is an integer number (2712887934).

Almost surely, 2^21003003312 is an apocalyptic number.

It is an amenable number.

21003003312 is an abundant number, since it is smaller than the sum of its proper divisors (33254755368).

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

21003003312 is a wasteful number, since it uses less digits than its factorization.

21003003312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437562580 (or 437562574 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 15.

Adding to 21003003312 its reverse (21330030012), we get a palindrome (42333033324).

The spelling of 21003003312 in words is "twenty-one billion, three million, three thousand, three hundred twelve".