21013001212 has 24 divisors (see below), whose sum is σ = 42055007456. Its totient is φ = 8999356608.

The previous prime is 21013001201. The next prime is 21013001231. The reversal of 21013001212 is 21210031012.

It is a junction number, because it is equal to n+sod(n) for n = 21013001192 and 21013001201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 217563 + ... + 298930.

Almost surely, 2^21013001212 is an apocalyptic number.

It is an amenable number.

21013001212 is an abundant number, since it is smaller than the sum of its proper divisors (21042006244).

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

21013001212 is a wasteful number, since it uses less digits than its factorization.

21013001212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 517957 (or 517955 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21013001212 its reverse (21210031012), we get a palindrome (42223032224).

The spelling of 21013001212 in words is "twenty-one billion, thirteen million, one thousand, two hundred twelve".