77813144640 has 1680 divisors, whose sum is σ = 363353786880. Its totient is φ = 15647385600.

The previous prime is 77813144627. The next prime is 77813144641. The reversal of 77813144640 is 4644131877.

77813144640 is a `hidden beast` number, since 7 + 78 + 131 + 446 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1680).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77813144641) by changing a digit.

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 239 ways as a sum of consecutive naturals, for example, 2510101425 + ... + 2510101455.

It is an arithmetic number, because the mean of its divisors is an integer number (216282016).

Almost surely, 2^77813144640 is an apocalyptic number.

77813144640 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77813144640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (181676893440).

77813144640 is an abundant number, since it is smaller than the sum of its proper divisors (285540642240).

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

77813144640 is a wasteful number, since it uses less digits than its factorization.

77813144640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107 (or 59 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 45.

The spelling of 77813144640 in words is "seventy-seven billion, eight hundred thirteen million, one hundred forty-four thousand, six hundred forty".