21013002012 has 12 divisors (see below), whose sum is σ = 49030338056. Its totient is φ = 7004334000.

The previous prime is 21013002011. The next prime is 21013002013. The reversal of 21013002012 is 21020031012.

It is an interprime number because it is at equal distance from previous prime (21013002011) and next prime (21013002013).

It is a tau number, because it is divible by the number of its divisors (12).

It is a Harshad number since it is a multiple of its sum of digits (12), and also a Moran number because the ratio is a prime number: 1751083501 = 21013002012 / (2 + 1 + 0 + 1 + 3 + 0 + 0 + 2 + 0 + 1 + 2).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21013002011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 875541739 + ... + 875541762.

Almost surely, 2^21013002012 is an apocalyptic number.

It is an amenable number.

21013002012 is an abundant number, since it is smaller than the sum of its proper divisors (28017336044).

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

21013002012 is a wasteful number, since it uses less digits than its factorization.

21013002012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1751083508 (or 1751083506 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 21013002012 its reverse (21020031012), we get a palindrome (42033033024).

The spelling of 21013002012 in words is "twenty-one billion, thirteen million, two thousand, twelve".