77564712640 has 28 divisors (see below), whose sum is σ = 184700972736. Its totient is φ = 31025884928.

The previous prime is 77564712613. The next prime is 77564712649. The reversal of 77564712640 is 4621746577.

It is not an unprimeable number, because it can be changed into a prime (77564712649) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 121194544 + ... + 121195183.

It is an arithmetic number, because the mean of its divisors is an integer number (6596463312).

Almost surely, 2^77564712640 is an apocalyptic number.

It is an amenable number.

77564712640 is an abundant number, since it is smaller than the sum of its proper divisors (107136260096).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77564712640 is a wasteful number, since it uses less digits than its factorization.

77564712640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242389744 (or 242389734 counting only the distinct ones).

The product of its (nonzero) digits is 1975680, while the sum is 49.

The spelling of 77564712640 in words is "seventy-seven billion, five hundred sixty-four million, seven hundred twelve thousand, six hundred forty".