77645382578 has 8 divisors (see below), whose sum is σ = 116492387868. Its totient is φ = 38814586624.

The previous prime is 77645382559. The next prime is 77645382587. The reversal of 77645382578 is 87528354677.

It can be written as a sum of positive squares in 2 ways, for example, as 59747491489 + 17897891089 = 244433^2 + 133783^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 77645382578.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4040351 + ... + 4059522.

Almost surely, 2^77645382578 is an apocalyptic number.

77645382578 is a deficient number, since it is larger than the sum of its proper divisors (38847005290).

77645382578 is a wasteful number, since it uses less digits than its factorization.

77645382578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8104668.

The product of its digits is 79027200, while the sum is 62.

The spelling of 77645382578 in words is "seventy-seven billion, six hundred forty-five million, three hundred eighty-two thousand, five hundred seventy-eight".