77746646640 has 320 divisors, whose sum is σ = 268718800896. Its totient is φ = 18470301696.

The previous prime is 77746646617. The next prime is 77746646657. The reversal of 77746646640 is 4664664777.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 14658229 + ... + 14663531.

Almost surely, 2^77746646640 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 77746646640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (134359400448).

77746646640 is an abundant number, since it is smaller than the sum of its proper divisors (190972154256).

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

77746646640 is a wasteful number, since it uses less digits than its factorization.

77746646640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5496 (or 5490 counting only the distinct ones).

The product of its (nonzero) digits is 28449792, while the sum is 57.

The spelling of 77746646640 in words is "seventy-seven billion, seven hundred forty-six million, six hundred forty-six thousand, six hundred forty".