16531851819844 has 9 divisors (see below), whose sum is σ = 28930754915517. Its totient is φ = 8265921843984.

The previous prime is 16531851819839. The next prime is 16531851819919. The reversal of 16531851819844 is 44891815813561.

It is a happy number.

The square root of 16531851819844 is 4065938.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 11471511589444 + 5060340230400 = 3386962^2 + 2249520^2 .

It is a Duffinian 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 2 ways as a sum of consecutive naturals, for example, 7115392 + ... + 9148360.

Almost surely, 2^{16531851819844} is an apocalyptic number.

16531851819844 is the 4065938-th square number.

It is an amenable number.

16531851819844 is a deficient number, since it is larger than the sum of its proper divisors (12398903095673).

16531851819844 is an frugal number, since it uses more digits than its factorization.

16531851819844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4065942 (or 2032971 counting only the distinct ones).

The product of its digits is 33177600, while the sum is 64.

The spelling of 16531851819844 in words is "sixteen trillion, five hundred thirty-one billion, eight hundred fifty-one million, eight hundred nineteen thousand, eight hundred forty-four".