16243564565 has 8 divisors (see below), whose sum is σ = 19492991448. Its totient is φ = 12994375680.

The previous prime is 16243564553. The next prime is 16243564573. The reversal of 16243564565 is 56546534261.

It can be written as a sum of positive squares in 4 ways, for example, as 2024910001 + 14218654564 = 44999^2 + 119242^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 16243564565 - 2⁶ = 16243564501 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 173885 + ... + 250445.

It is an arithmetic number, because the mean of its divisors is an integer number (2436623931).

Almost surely, 2^16243564565 is an apocalyptic number.

It is an amenable number.

16243564565 is a deficient number, since it is larger than the sum of its proper divisors (3249426883).

16243564565 is an equidigital number, since it uses as much as digits as its factorization.

16243564565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118999.

The product of its digits is 2592000, while the sum is 47.

The spelling of 16243564565 in words is "sixteen billion, two hundred forty-three million, five hundred sixty-four thousand, five hundred sixty-five".