66776514127709 has 4 divisors (see below), whose sum is σ = 67400593699104. Its totient is φ = 66152434556316.

The previous prime is 66776514127667. The next prime is 66776514127727. The reversal of 66776514127709 is 90772141567766.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66776514127709 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 (66776514127409) 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, 312039785537 + ... + 312039785750.

It is an arithmetic number, because the mean of its divisors is an integer number (16850148424776).

Almost surely, 2^{66776514127709} is an apocalyptic number.

It is an amenable number.

66776514127709 is a deficient number, since it is larger than the sum of its proper divisors (624079571395).

66776514127709 is a wasteful number, since it uses less digits than its factorization.

66776514127709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 624079571394.

The product of its (nonzero) digits is 186701760, while the sum is 68.

The spelling of 66776514127709 in words is "sixty-six trillion, seven hundred seventy-six billion, five hundred fourteen million, one hundred twenty-seven thousand, seven hundred nine".