21243344144 has 20 divisors (see below), whose sum is σ = 44900705040. Its totient is φ = 9656065440.

The previous prime is 21243344141. The next prime is 21243344147. The reversal of 21243344144 is 44144334212.

It is an interprime number because it is at equal distance from previous prime (21243344141) and next prime (21243344147).

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 21243344144.

It is not an unprimeable number, because it can be changed into a prime (21243344141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60350234 + ... + 60350585.

It is an arithmetic number, because the mean of its divisors is an integer number (2245035252).

Almost surely, 2^21243344144 is an apocalyptic number.

It is an amenable number.

21243344144 is an abundant number, since it is smaller than the sum of its proper divisors (23657360896).

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

21243344144 is a wasteful number, since it uses less digits than its factorization.

21243344144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120700838 (or 120700832 counting only the distinct ones).

The product of its digits is 36864, while the sum is 32.

Adding to 21243344144 its reverse (44144334212), we get a palindrome (65387678356).

The spelling of 21243344144 in words is "twenty-one billion, two hundred forty-three million, three hundred forty-four thousand, one hundred forty-four".