21344131231 has 4 divisors (see below), whose sum is σ = 21344700472. Its totient is φ = 21343561992.

The previous prime is 21344131201. The next prime is 21344131273. The reversal of 21344131231 is 13213144312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21344131231 - 2¹⁹ = 21343606943 is a prime.

It is a super-2 number, since 2×21344131231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21344131196 and 21344131205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21344131201) 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, 224085 + ... + 304798.

It is an arithmetic number, because the mean of its divisors is an integer number (5336175118).

Almost surely, 2^21344131231 is an apocalyptic number.

21344131231 is a deficient number, since it is larger than the sum of its proper divisors (569241).

21344131231 is an equidigital number, since it uses as much as digits as its factorization.

21344131231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 569240.

The product of its digits is 1728, while the sum is 25.

Adding to 21344131231 its reverse (13213144312), we get a palindrome (34557275543).

The spelling of 21344131231 in words is "twenty-one billion, three hundred forty-four million, one hundred thirty-one thousand, two hundred thirty-one".