77684246640 has 2560 divisors, whose sum is σ = 396774604800. Its totient is φ = 13436928000.

The previous prime is 77684246623. The next prime is 77684246687. The reversal of 77684246640 is 4664248677.

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 511 ways as a sum of consecutive naturals, for example, 1273512210 + ... + 1273512270.

It is an arithmetic number, because the mean of its divisors is an integer number (154990080).

Almost surely, 2^77684246640 is an apocalyptic number.

77684246640 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 77684246640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (198387302400).

77684246640 is an abundant number, since it is smaller than the sum of its proper divisors (319090358160).

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

77684246640 is a wasteful number, since it uses less digits than its factorization.

77684246640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164 (or 152 counting only the distinct ones).

The product of its (nonzero) digits is 10838016, while the sum is 54.

The spelling of 77684246640 in words is "seventy-seven billion, six hundred eighty-four million, two hundred forty-six thousand, six hundred forty".