21451033240405 has 8 divisors (see below), whose sum is σ = 27096041988000. Its totient is φ = 16257625192656.

The previous prime is 21451033240361. The next prime is 21451033240421. The reversal of 21451033240405 is 50404233015412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21451033240405 - 2²⁹ = 21450496369493 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 112900174855 + ... + 112900175044.

It is an arithmetic number, because the mean of its divisors is an integer number (3387005248500).

Almost surely, 2^{21451033240405} is an apocalyptic number.

It is an amenable number.

21451033240405 is a deficient number, since it is larger than the sum of its proper divisors (5645008747595).

21451033240405 is a wasteful number, since it uses less digits than its factorization.

21451033240405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 225800349923.

The product of its (nonzero) digits is 57600, while the sum is 34.

Adding to 21451033240405 its reverse (50404233015412), we get a palindrome (71855266255817).

The spelling of 21451033240405 in words is "twenty-one trillion, four hundred fifty-one billion, thirty-three million, two hundred forty thousand, four hundred five".