65166768077 has 4 divisors (see below), whose sum is σ = 65205261660. Its totient is φ = 65128274496.

The previous prime is 65166768071. The next prime is 65166768091. The reversal of 65166768077 is 77086766156.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 21781627396 + 43385140681 = 147586^2 + 208291^2 .

It is a cyclic number.

It is not a de Polignac number, because 65166768077 - 2⁴ = 65166768061 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 (65166768071) 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, 19244252 + ... + 19247637.

It is an arithmetic number, because the mean of its divisors is an integer number (16301315415).

Almost surely, 2^65166768077 is an apocalyptic number.

It is an amenable number.

65166768077 is a deficient number, since it is larger than the sum of its proper divisors (38493583).

65166768077 is a wasteful number, since it uses less digits than its factorization.

65166768077 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38493582.

The product of its (nonzero) digits is 17781120, while the sum is 59.

The spelling of 65166768077 in words is "sixty-five billion, one hundred sixty-six million, seven hundred sixty-eight thousand, seventy-seven".