21569536416 has 24 divisors (see below), whose sum is σ = 56620033344. Its totient is φ = 7189845440.

The previous prime is 21569536411. The next prime is 21569536423. The reversal of 21569536416 is 61463596512.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (21569536411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112341240 + ... + 112341431.

It is an arithmetic number, because the mean of its divisors is an integer number (2359168056).

Almost surely, 2^21569536416 is an apocalyptic number.

It is an amenable number.

21569536416 is an abundant number, since it is smaller than the sum of its proper divisors (35050496928).

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

21569536416 is a wasteful number, since it uses less digits than its factorization.

21569536416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224682684 (or 224682676 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 48.

The spelling of 21569536416 in words is "twenty-one billion, five hundred sixty-nine million, five hundred thirty-six thousand, four hundred sixteen".