21121020222012 has 72 divisors (see below), whose sum is σ = 58987606388256. Its totient is φ = 6338106660864.

The previous prime is 21121020221953. The next prime is 21121020222019. The reversal of 21121020222012 is 21022202012112.

It is a happy number.

21121020222012 is a `hidden beast` number, since 21 + 1 + 210 + 202 + 220 + 12 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121020222019) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 750235293 + ... + 750263444.

It is an arithmetic number, because the mean of its divisors is an integer number (819272310948).

Almost surely, 2^{21121020222012} is an apocalyptic number.

It is an amenable number.

21121020222012 is an abundant number, since it is smaller than the sum of its proper divisors (37866586166244).

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

21121020222012 is a wasteful number, since it uses less digits than its factorization.

21121020222012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1500498787 (or 1500498782 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21121020222012 its reverse (21022202012112), we get a palindrome (42143222234124).

The spelling of 21121020222012 in words is "twenty-one trillion, one hundred twenty-one billion, twenty million, two hundred twenty-two thousand, twelve".