21445205315424 has 96 divisors (see below), whose sum is σ = 61681804684416. Its totient is φ = 6469919032320.

The previous prime is 21445205315423. The next prime is 21445205315441. The reversal of 21445205315424 is 42451350254412.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21445205315423) 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 15 ways as a sum of consecutive naturals, for example, 44491477 + ... + 44970900.

It is an arithmetic number, because the mean of its divisors is an integer number (642518798796).

Almost surely, 2^{21445205315424} is an apocalyptic number.

21445205315424 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21445205315424 is an abundant number, since it is smaller than the sum of its proper divisors (40236599368992).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21445205315424 is a wasteful number, since it uses less digits than its factorization.

21445205315424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89462628 (or 89462620 counting only the distinct ones).

The product of its (nonzero) digits is 768000, while the sum is 42.

Adding to 21445205315424 its reverse (42451350254412), we get a palindrome (63896555569836).

The spelling of 21445205315424 in words is "twenty-one trillion, four hundred forty-five billion, two hundred five million, three hundred fifteen thousand, four hundred twenty-four".