21012021211212 has 18 divisors (see below), whose sum is σ = 53113720283988. Its totient is φ = 7004007070392.

The previous prime is 21012021211193. The next prime is 21012021211331. The reversal of 21012021211212 is 21211212021012.

21012021211212 is a `hidden beast` number, since 210 + 1 + 20 + 212 + 11 + 212 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 291833627898 + ... + 291833627969.

Almost surely, 2^{21012021211212} is an apocalyptic number.

It is an amenable number.

21012021211212 is an abundant number, since it is smaller than the sum of its proper divisors (32101699072776).

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

21012021211212 is a wasteful number, since it uses less digits than its factorization.

21012021211212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 583667255877 (or 583667255872 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21012021211212 its reverse (21211212021012), we get a palindrome (42223233232224).

The spelling of 21012021211212 in words is "twenty-one trillion, twelve billion, twenty-one million, two hundred eleven thousand, two hundred twelve".