21113131344 has 20 divisors (see below), whose sum is σ = 54542256096. Its totient is φ = 7037710432.

The previous prime is 21113131339. The next prime is 21113131349. The reversal of 21113131344 is 44313131112.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21113131339) and next prime (21113131349).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113131349) 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, 219928404 + ... + 219928499.

Almost surely, 2^21113131344 is an apocalyptic number.

21113131344 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21113131344 is an abundant number, since it is smaller than the sum of its proper divisors (33429124752).

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

21113131344 is a wasteful number, since it uses less digits than its factorization.

21113131344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439856914 (or 439856908 counting only the distinct ones).

The product of its digits is 864, while the sum is 24.

Adding to 21113131344 its reverse (44313131112), we get a palindrome (65426262456).

The spelling of 21113131344 in words is "twenty-one billion, one hundred thirteen million, one hundred thirty-one thousand, three hundred forty-four".