21012002112 has 84 divisors (see below), whose sum is σ = 58674463296. Its totient is φ = 6635347200.

The previous prime is 21012002047. The next prime is 21012002117. The reversal of 21012002112 is 21120021012.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012002117) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 82264 + ... + 220887.

Almost surely, 2^21012002112 is an apocalyptic number.

It is an amenable number.

21012002112 is an abundant number, since it is smaller than the sum of its proper divisors (37662461184).

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

21012002112 is a wasteful number, since it uses less digits than its factorization.

21012002112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303204 (or 303175 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21012002112 its reverse (21120021012), we get a palindrome (42132023124).

The spelling of 21012002112 in words is "twenty-one billion, twelve million, two thousand, one hundred twelve".