77664617 has 4 divisors (see below), whose sum is σ = 77796180. Its totient is φ = 77533056.

The previous prime is 77664607. The next prime is 77664623. The reversal of 77664617 is 71646677.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71646677 = 8191 ⋅8747.

It can be written as a sum of positive squares in 2 ways, for example, as 63744256 + 13920361 = 7984^2 + 3731^2 .

It is a cyclic number.

It is not a de Polignac number, because 77664617 - 2⁸ = 77664361 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77664607) 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, 64892 + ... + 66077.

It is an arithmetic number, because the mean of its divisors is an integer number (19449045).

Almost surely, 2^77664617 is an apocalyptic number.

It is an amenable number.

77664617 is a deficient number, since it is larger than the sum of its proper divisors (131563).

77664617 is a wasteful number, since it uses less digits than its factorization.

77664617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131562.

The product of its digits is 296352, while the sum is 44.

The square root of 77664617 is about 8812.7530885643. The cubic root of 77664617 is about 426.6526049918.

The spelling of 77664617 in words is "seventy-seven million, six hundred sixty-four thousand, six hundred seventeen".