21404243041 has 4 divisors (see below), whose sum is σ = 21404654784. Its totient is φ = 21403831300.

The previous prime is 21404243039. The next prime is 21404243051. The reversal of 21404243041 is 14034240412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21404243041 - 2¹ = 21404243039 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21404242997 and 21404243015.

It is not an unprimeable number, because it can be changed into a prime (21404243051) 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, 114325 + ... + 236386.

It is an arithmetic number, because the mean of its divisors is an integer number (5351163696).

Almost surely, 2^21404243041 is an apocalyptic number.

It is an amenable number.

21404243041 is a deficient number, since it is larger than the sum of its proper divisors (411743).

21404243041 is an equidigital number, since it uses as much as digits as its factorization.

21404243041 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 411742.

The product of its (nonzero) digits is 3072, while the sum is 25.

Adding to 21404243041 its reverse (14034240412), we get a palindrome (35438483453).

The spelling of 21404243041 in words is "twenty-one billion, four hundred four million, two hundred forty-three thousand, forty-one".