21421344412 has 24 divisors (see below), whose sum is σ = 40548863376. Its totient is φ = 9843214848.

The previous prime is 21421344383. The next prime is 21421344449. The reversal of 21421344412 is 21444312412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 895573 + ... + 919180.

It is an arithmetic number, because the mean of its divisors is an integer number (1689535974).

Almost surely, 2^21421344412 is an apocalyptic number.

It is an amenable number.

21421344412 is a deficient number, since it is larger than the sum of its proper divisors (19127518964).

21421344412 is a wasteful number, since it uses less digits than its factorization.

21421344412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1814997 (or 1814995 counting only the distinct ones).

The product of its digits is 6144, while the sum is 28.

Adding to 21421344412 its reverse (21444312412), we get a palindrome (42865656824).

The spelling of 21421344412 in words is "twenty-one billion, four hundred twenty-one million, three hundred forty-four thousand, four hundred twelve".