77665216606 has 4 divisors (see below), whose sum is σ = 116497824912. Its totient is φ = 38832608302.

The previous prime is 77665216549. The next prime is 77665216609. The reversal of 77665216606 is 60661256677.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60661256677 = 7 ⋅8665893811.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77665216609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19416304150 + ... + 19416304153.

It is an arithmetic number, because the mean of its divisors is an integer number (29124456228).

Almost surely, 2^77665216606 is an apocalyptic number.

77665216606 is a deficient number, since it is larger than the sum of its proper divisors (38832608306).

77665216606 is a wasteful number, since it uses less digits than its factorization.

77665216606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38832608305.

The product of its (nonzero) digits is 3810240, while the sum is 52.

The spelling of 77665216606 in words is "seventy-seven billion, six hundred sixty-five million, two hundred sixteen thousand, six hundred six".