77937949656 has 256 divisors, whose sum is σ = 257466470400. Its totient is φ = 21381954048.

The previous prime is 77937949643. The next prime is 77937949681. The reversal of 77937949656 is 65694973977.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3756046 + ... + 3776738.

It is an arithmetic number, because the mean of its divisors is an integer number (1005728400).

Almost surely, 2^77937949656 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 77937949656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (128733235200).

77937949656 is an abundant number, since it is smaller than the sum of its proper divisors (179528520744).

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

77937949656 is a wasteful number, since it uses less digits than its factorization.

77937949656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20815 (or 20805 counting only the distinct ones).

The product of its digits is 540101520, while the sum is 72.

The spelling of 77937949656 in words is "seventy-seven billion, nine hundred thirty-seven million, nine hundred forty-nine thousand, six hundred fifty-six".