66656650005 has 60 divisors (see below), whose sum is σ = 131338384716. Its totient is φ = 32318352000.

The previous prime is 66656649937. The next prime is 66656650013. The reversal of 66656650005 is 50005665666.

It can be written as a sum of positive squares in 2 ways, for example, as 43140120804 + 23516529201 = 207702^2 + 153351^2 .

It is not a de Polignac number, because 66656650005 - 2²⁵ = 66623095573 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 631096 + ... + 729105.

Almost surely, 2^66656650005 is an apocalyptic number.

It is an amenable number.

66656650005 is a deficient number, since it is larger than the sum of its proper divisors (64681734711).

66656650005 is a wasteful number, since it uses less digits than its factorization.

66656650005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1360240 (or 1360220 counting only the distinct ones).

The product of its (nonzero) digits is 972000, while the sum is 45.

The spelling of 66656650005 in words is "sixty-six billion, six hundred fifty-six million, six hundred fifty thousand, five".