77647458816 has 640 divisors, whose sum is σ = 250783948800. Its totient is φ = 23668899840.

The previous prime is 77647458797. The next prime is 77647458841. The reversal of 77647458816 is 61885474677.

77647458816 is a `hidden beast` number, since 7 + 7 + 6 + 47 + 4 + 588 + 1 + 6 = 666.

It is a super-2 number, since 2×77647458816² (a number of 23 digits) contains 22 as substring.

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, 935511511 + ... + 935511593.

It is an arithmetic number, because the mean of its divisors is an integer number (391849920).

Almost surely, 2^77647458816 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 77647458816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125391974400).

77647458816 is an abundant number, since it is smaller than the sum of its proper divisors (173136489984).

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

77647458816 is a wasteful number, since it uses less digits than its factorization.

77647458816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237 (or 215 counting only the distinct ones).

The product of its digits is 63221760, while the sum is 63.

The spelling of 77647458816 in words is "seventy-seven billion, six hundred forty-seven million, four hundred fifty-eight thousand, eight hundred sixteen".