66401076677 has 4 divisors (see below), whose sum is σ = 71508851820. Its totient is φ = 61293301536.

The previous prime is 66401076673. The next prime is 66401076757. The reversal of 66401076677 is 77667010466.

66401076677 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 36649656481 + 29751420196 = 191441^2 + 172486^2 .

It is a cyclic number.

It is not a de Polignac number, because 66401076677 - 2² = 66401076673 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 (66401076673) 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, 2553887552 + ... + 2553887577.

It is an arithmetic number, because the mean of its divisors is an integer number (17877212955).

Almost surely, 2^66401076677 is an apocalyptic number.

It is an amenable number.

66401076677 is a deficient number, since it is larger than the sum of its proper divisors (5107775143).

66401076677 is a wasteful number, since it uses less digits than its factorization.

66401076677 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5107775142.

The product of its (nonzero) digits is 1778112, while the sum is 50.

The spelling of 66401076677 in words is "sixty-six billion, four hundred one million, seventy-six thousand, six hundred seventy-seven".