21112443412 has 24 divisors (see below), whose sum is σ = 39178328616. Its totient is φ = 9920483328.

The previous prime is 21112443403. The next prime is 21112443419. The reversal of 21112443412 is 21434421112.

It can be written as a sum of positive squares in 4 ways, for example, as 4760172036 + 16352271376 = 68994^2 + 127876^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112443419) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 184903 + ... + 276430.

It is an arithmetic number, because the mean of its divisors is an integer number (1632430359).

Almost surely, 2^21112443412 is an apocalyptic number.

It is an amenable number.

21112443412 is a deficient number, since it is larger than the sum of its proper divisors (18065885204).

21112443412 is a wasteful number, since it uses less digits than its factorization.

21112443412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 462027 (or 462025 counting only the distinct ones).

The product of its digits is 1536, while the sum is 25.

Adding to 21112443412 its reverse (21434421112), we get a palindrome (42546864524).

The spelling of 21112443412 in words is "twenty-one billion, one hundred twelve million, four hundred forty-three thousand, four hundred twelve".