21043024447 has 2 divisors, whose sum is σ = 21043024448. Its totient is φ = 21043024446.

The previous prime is 21043024391. The next prime is 21043024487. The reversal of 21043024447 is 74442034012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21043024447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21043024487) 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 as a sum of consecutive naturals, namely, 10521512223 + 10521512224.

It is an arithmetic number, because the mean of its divisors is an integer number (10521512224).

Almost surely, 2^21043024447 is an apocalyptic number.

21043024447 is a deficient number, since it is larger than the sum of its proper divisors (1).

21043024447 is an equidigital number, since it uses as much as digits as its factorization.

21043024447 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21504, while the sum is 31.

Adding to 21043024447 its reverse (74442034012), we get a palindrome (95485058459).

The spelling of 21043024447 in words is "twenty-one billion, forty-three million, twenty-four thousand, four hundred forty-seven".