77779937664 has 1024 divisors, whose sum is σ = 286651008000. Its totient is φ = 20692869120.

The previous prime is 77779937647. The next prime is 77779937671. The reversal of 77779937664 is 46673997777.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 77779937592 and 77779937601.

It is a congruent number.

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 127 ways as a sum of consecutive naturals, for example, 1160894559 + ... + 1160894625.

It is an arithmetic number, because the mean of its divisors is an integer number (279932625).

Almost surely, 2^77779937664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77779937664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143325504000).

77779937664 is an abundant number, since it is smaller than the sum of its proper divisors (208871070336).

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

77779937664 is a wasteful number, since it uses less digits than its factorization.

77779937664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155 (or 125 counting only the distinct ones).

The product of its digits is 588110544, while the sum is 72.

The spelling of 77779937664 in words is "seventy-seven billion, seven hundred seventy-nine million, nine hundred thirty-seven thousand, six hundred sixty-four".