21131424040043 has 4 divisors (see below), whose sum is σ = 21368855770920. Its totient is φ = 20893992309168.

The previous prime is 21131424039983. The next prime is 21131424040127. The reversal of 21131424040043 is 34004042413112.

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 21131424040043 - 2²⁴ = 21131407262827 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21131424039988 and 21131424040015.

It is not an unprimeable number, because it can be changed into a prime (21131424040343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 118715865305 + ... + 118715865482.

It is an arithmetic number, because the mean of its divisors is an integer number (5342213942730).

Almost surely, 2^{21131424040043} is an apocalyptic number.

21131424040043 is a deficient number, since it is larger than the sum of its proper divisors (237431730877).

21131424040043 is an equidigital number, since it uses as much as digits as its factorization.

21131424040043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237431730876.

The product of its (nonzero) digits is 9216, while the sum is 29.

Adding to 21131424040043 its reverse (34004042413112), we get a palindrome (55135466453155).

The spelling of 21131424040043 in words is "twenty-one trillion, one hundred thirty-one billion, four hundred twenty-four million, forty thousand, forty-three".