66717644012077 has 4 divisors (see below), whose sum is σ = 66747874029696. Its totient is φ = 66687413994460.

The previous prime is 66717644012029. The next prime is 66717644012147. The reversal of 66717644012077 is 77021044671766.

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-66717644012077 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 (66717944012077) 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, 15115005499 + ... + 15115009912.

It is an arithmetic number, because the mean of its divisors is an integer number (16686968507424).

Almost surely, 2^{66717644012077} is an apocalyptic number.

It is an amenable number.

66717644012077 is a deficient number, since it is larger than the sum of its proper divisors (30230017619).

66717644012077 is a wasteful number, since it uses less digits than its factorization.

66717644012077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30230017618.

The product of its (nonzero) digits is 16595712, while the sum is 58.

The spelling of 66717644012077 in words is "sixty-six trillion, seven hundred seventeen billion, six hundred forty-four million, twelve thousand, seventy-seven".