77381553646 has 16 divisors (see below), whose sum is σ = 116594755200. Its totient is φ = 38516948280.

The previous prime is 77381553637. The next prime is 77381553661. The reversal of 77381553646 is 64635518377.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 420255 + ... + 575653.

It is an arithmetic number, because the mean of its divisors is an integer number (7287172200).

Almost surely, 2^77381553646 is an apocalyptic number.

77381553646 is a deficient number, since it is larger than the sum of its proper divisors (39213201554).

77381553646 is a wasteful number, since it uses less digits than its factorization.

77381553646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156519.

The product of its digits is 12700800, while the sum is 55.

The spelling of 77381553646 in words is "seventy-seven billion, three hundred eighty-one million, five hundred fifty-three thousand, six hundred forty-six".