66365306563 has 16 divisors (see below), whose sum is σ = 69635681280. Its totient is φ = 63166836096.

The previous prime is 66365306561. The next prime is 66365306591. The reversal of 66365306563 is 36560356366.

It is a cyclic number.

It is not a de Polignac number, because 66365306563 - 2¹ = 66365306561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66365306561) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 520845 + ... + 635617.

It is an arithmetic number, because the mean of its divisors is an integer number (4352230080).

Almost surely, 2^66365306563 is an apocalyptic number.

66365306563 is a deficient number, since it is larger than the sum of its proper divisors (3270374717).

66365306563 is a wasteful number, since it uses less digits than its factorization.

66365306563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115086.

The product of its (nonzero) digits is 5248800, while the sum is 49.

The spelling of 66365306563 in words is "sixty-six billion, three hundred sixty-five million, three hundred six thousand, five hundred sixty-three".