21012121012012 has 12 divisors (see below), whose sum is σ = 39599766522736. Its totient is φ = 9697902005520.

The previous prime is 21012121011991. The next prime is 21012121012013. The reversal of 21012121012012 is 21021012121012.

It is not an unprimeable number, because it can be changed into a prime (21012121012013) 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, 202039625064 + ... + 202039625167.

Almost surely, 2^{21012121012012} is an apocalyptic number.

It is an amenable number.

21012121012012 is a deficient number, since it is larger than the sum of its proper divisors (18587645510724).

21012121012012 is a wasteful number, since it uses less digits than its factorization.

21012121012012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404079250248 (or 404079250246 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21012121012012 its reverse (21021012121012), we get a palindrome (42033133133024).

The spelling of 21012121012012 in words is "twenty-one trillion, twelve billion, one hundred twenty-one million, twelve thousand, twelve".