66510555550603 has 4 divisors (see below), whose sum is σ = 66594006687600. Its totient is φ = 66427104413608.

The previous prime is 66510555550601. The next prime is 66510555550609. The reversal of 66510555550603 is 30605555501566.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66510555550603 - 2¹ = 66510555550601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66510555550601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41725567303 + ... + 41725568896.

It is an arithmetic number, because the mean of its divisors is an integer number (16648501671900).

Almost surely, 2^{66510555550603} is an apocalyptic number.

66510555550603 is a deficient number, since it is larger than the sum of its proper divisors (83451136997).

66510555550603 is an equidigital number, since it uses as much as digits as its factorization.

66510555550603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83451136996.

The product of its (nonzero) digits is 10125000, while the sum is 52.

The spelling of 66510555550603 in words is "sixty-six trillion, five hundred ten billion, five hundred fifty-five million, five hundred fifty thousand, six hundred three".