21255223044012 has 48 divisors (see below), whose sum is σ = 50938438854912. Its totient is φ = 6893247648960.

The previous prime is 21255223043969. The next prime is 21255223044191. The reversal of 21255223044012 is 21044032255212.

It is a super-2 number, since 2×21255223044012² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7965937 + ... + 10294007.

It is an arithmetic number, because the mean of its divisors is an integer number (1061217476144).

Almost surely, 2^{21255223044012} is an apocalyptic number.

It is an amenable number.

21255223044012 is an abundant number, since it is smaller than the sum of its proper divisors (29683215810900).

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

21255223044012 is a wasteful number, since it uses less digits than its factorization.

21255223044012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2348678 (or 2348676 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 33.

Adding to 21255223044012 its reverse (21044032255212), we get a palindrome (42299255299224).

The spelling of 21255223044012 in words is "twenty-one trillion, two hundred fifty-five billion, two hundred twenty-three million, forty-four thousand, twelve".