28753726565 has 8 divisors (see below), whose sum is σ = 35437025400. Its totient is φ = 22381278912.

The previous prime is 28753726553. The next prime is 28753726571. The reversal of 28753726565 is 56562735782.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 14613424996 + 14140301569 = 120886^2 + 118913^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 28753726565 - 2¹² = 28753722469 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28753726565.

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, 77712590 + ... + 77712959.

It is an arithmetic number, because the mean of its divisors is an integer number (4429628175).

Almost surely, 2^28753726565 is an apocalyptic number.

It is an amenable number.

28753726565 is a deficient number, since it is larger than the sum of its proper divisors (6683298835).

28753726565 is a wasteful number, since it uses less digits than its factorization.

28753726565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155425591.

The product of its digits is 21168000, while the sum is 56.

The spelling of 28753726565 in words is "twenty-eight billion, seven hundred fifty-three million, seven hundred twenty-six thousand, five hundred sixty-five".