77620681944 has 240 divisors, whose sum is σ = 237316273920. Its totient is φ = 23690983680.

The previous prime is 77620681933. The next prime is 77620681967. The reversal of 77620681944 is 44918602677.

77620681944 is a `hidden beast` number, since 7 + 7 + 620 + 6 + 8 + 1 + 9 + 4 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 13905234 + ... + 13910814.

It is an arithmetic number, because the mean of its divisors is an integer number (988817808).

Almost surely, 2^77620681944 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 77620681944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118658136960).

77620681944 is an abundant number, since it is smaller than the sum of its proper divisors (159695591976).

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

77620681944 is a wasteful number, since it uses less digits than its factorization.

77620681944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5752 (or 5726 counting only the distinct ones).

The product of its (nonzero) digits is 4064256, while the sum is 54.

The spelling of 77620681944 in words is "seventy-seven billion, six hundred twenty million, six hundred eighty-one thousand, nine hundred forty-four".