77617556647 has 4 divisors (see below), whose sum is σ = 77686306720. Its totient is φ = 77548806576.

The previous prime is 77617556629. The next prime is 77617556657. The reversal of 77617556647 is 74665571677.

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

It is a cyclic number.

It is not a de Polignac number, because 77617556647 - 2¹⁹ = 77617032359 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 (77617556657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34373343 + ... + 34375600.

It is an arithmetic number, because the mean of its divisors is an integer number (19421576680).

Almost surely, 2^77617556647 is an apocalyptic number.

77617556647 is a deficient number, since it is larger than the sum of its proper divisors (68750073).

77617556647 is a wasteful number, since it uses less digits than its factorization.

77617556647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68750072.

The product of its digits is 51861600, while the sum is 61.

The spelling of 77617556647 in words is "seventy-seven billion, six hundred seventeen million, five hundred fifty-six thousand, six hundred forty-seven".