77634645215 has 4 divisors (see below), whose sum is σ = 93161574264. Its totient is φ = 62107716168.

The previous prime is 77634645181. The next prime is 77634645217. The reversal of 77634645215 is 51254643677.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 51254643677 = 21751 ⋅2356427.

It is a cyclic number.

It is not a de Polignac number, because 77634645215 - 2¹⁶ = 77634579679 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 (77634645217) 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, 7763464517 + ... + 7763464526.

It is an arithmetic number, because the mean of its divisors is an integer number (23290393566).

Almost surely, 2^77634645215 is an apocalyptic number.

77634645215 is a deficient number, since it is larger than the sum of its proper divisors (15526929049).

77634645215 is a wasteful number, since it uses less digits than its factorization.

77634645215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15526929048.

The product of its digits is 4233600, while the sum is 50.

The spelling of 77634645215 in words is "seventy-seven billion, six hundred thirty-four million, six hundred forty-five thousand, two hundred fifteen".