66664263713 has 4 divisors (see below), whose sum is σ = 66682397460. Its totient is φ = 66646129968.

The previous prime is 66664263671. The next prime is 66664263739. The reversal of 66664263713 is 31736246666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31736246666 = 2 ⋅15868123333.

It can be written as a sum of positive squares in 2 ways, for example, as 58928533504 + 7735730209 = 242752^2 + 87953^2 .

It is a cyclic number.

It is not a de Polignac number, because 66664263713 - 2³² = 62369296417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66664203713) 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, 9061358 + ... + 9068711.

It is an arithmetic number, because the mean of its divisors is an integer number (16670599365).

Almost surely, 2^66664263713 is an apocalyptic number.

It is an amenable number.

66664263713 is a deficient number, since it is larger than the sum of its proper divisors (18133747).

66664263713 is a wasteful number, since it uses less digits than its factorization.

66664263713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18133746.

The product of its digits is 3919104, while the sum is 50.

The spelling of 66664263713 in words is "sixty-six billion, six hundred sixty-four million, two hundred sixty-three thousand, seven hundred thirteen".