21204412112 has 20 divisors (see below), whose sum is σ = 44243821860. Its totient is φ = 9786651648.

The previous prime is 21204412111. The next prime is 21204412123. The reversal of 21204412112 is 21121440212.

It can be written as a sum of positive squares in 2 ways, for example, as 7779945616 + 13424466496 = 88204^2 + 115864^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21204412111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50971937 + ... + 50972352.

It is an arithmetic number, because the mean of its divisors is an integer number (2212191093).

Almost surely, 2^21204412112 is an apocalyptic number.

It is an amenable number.

21204412112 is an abundant number, since it is smaller than the sum of its proper divisors (23039409748).

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

21204412112 is a wasteful number, since it uses less digits than its factorization.

21204412112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101944310 (or 101944304 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 21204412112 its reverse (21121440212), we get a palindrome (42325852324).

The spelling of 21204412112 in words is "twenty-one billion, two hundred four million, four hundred twelve thousand, one hundred twelve".