21564433446512 has 80 divisors (see below), whose sum is σ = 47245569840000. Its totient is φ = 9445047601920.

The previous prime is 21564433446433. The next prime is 21564433446533.

21564433446512 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×21564433446512² (a number of 27 digits) contains 22 as substring.

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 15 ways as a sum of consecutive naturals, for example, 1686578 + ... + 6780369.

It is an arithmetic number, because the mean of its divisors is an integer number (590569623000).

Almost surely, 2^{21564433446512} is an apocalyptic number.

21564433446512 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21564433446512 is an abundant number, since it is smaller than the sum of its proper divisors (25681136393488).

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

21564433446512 is a wasteful number, since it uses less digits than its factorization.

21564433446512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8467494 (or 8467488 counting only the distinct ones).

The product of its digits is 8294400, while the sum is 50.

The spelling of 21564433446512 in words is "twenty-one trillion, five hundred sixty-four billion, four hundred thirty-three million, four hundred forty-six thousand, five hundred twelve".