66865658503 has 4 divisors (see below), whose sum is σ = 76417895440. Its totient is φ = 57313421568.

The previous prime is 66865658491. The next prime is 66865658521. The reversal of 66865658503 is 30585656866.

It is a happy number.

66865658503 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 66865658503 - 2⁵ = 66865658471 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66865658593) 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, 4776118458 + ... + 4776118471.

It is an arithmetic number, because the mean of its divisors is an integer number (19104473860).

Almost surely, 2^66865658503 is an apocalyptic number.

66865658503 is a deficient number, since it is larger than the sum of its proper divisors (9552236937).

66865658503 is an equidigital number, since it uses as much as digits as its factorization.

66865658503 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9552236936.

The product of its (nonzero) digits is 31104000, while the sum is 58.

The spelling of 66865658503 in words is "sixty-six billion, eight hundred sixty-five million, six hundred fifty-eight thousand, five hundred three".