21312201047424 has 128 divisors (see below), whose sum is σ = 64805408263680. Its totient is φ = 6079068057600.

The previous prime is 21312201047393. The next prime is 21312201047443. The reversal of 21312201047424 is 42474010221312.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 4980724 + ... + 8211699.

It is an arithmetic number, because the mean of its divisors is an integer number (506292252060).

Almost surely, 2^{21312201047424} is an apocalyptic number.

21312201047424 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21312201047424 is an abundant number, since it is smaller than the sum of its proper divisors (43493207216256).

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

21312201047424 is a wasteful number, since it uses less digits than its factorization.

21312201047424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13193048 (or 13193036 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 33.

Adding to 21312201047424 its reverse (42474010221312), we get a palindrome (63786211268736).

The spelling of 21312201047424 in words is "twenty-one trillion, three hundred twelve billion, two hundred one million, forty-seven thousand, four hundred twenty-four".