21120002012 has 12 divisors (see below), whose sum is σ = 37657362456. Its totient is φ = 10360755600.

The previous prime is 21120002009. The next prime is 21120002017. The reversal of 21120002012 is 21020002112.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21120001984 and 21120002002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120002017) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49811114 + ... + 49811537.

It is an arithmetic number, because the mean of its divisors is an integer number (3138113538).

Almost surely, 2^21120002012 is an apocalyptic number.

It is an amenable number.

21120002012 is a deficient number, since it is larger than the sum of its proper divisors (16537360444).

21120002012 is a wasteful number, since it uses less digits than its factorization.

21120002012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99622708 (or 99622706 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21120002012 its reverse (21020002112), we get a palindrome (42140004124).

The spelling of 21120002012 in words is "twenty-one billion, one hundred twenty million, two thousand, twelve".