77613646440 has 256 divisors, whose sum is σ = 274606848000. Its totient is φ = 17343175680.

The previous prime is 77613646391. The next prime is 77613646463. The reversal of 77613646440 is 4464631677.

It is a super-2 number, since 2×77613646440² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 77613646440.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 886141 + ... + 969779.

It is an arithmetic number, because the mean of its divisors is an integer number (1072683000).

Almost surely, 2^77613646440 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 77613646440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137303424000).

77613646440 is an abundant number, since it is smaller than the sum of its proper divisors (196993201560).

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

77613646440 is a wasteful number, since it uses less digits than its factorization.

77613646440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83720 (or 83716 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 48.

The spelling of 77613646440 in words is "seventy-seven billion, six hundred thirteen million, six hundred forty-six thousand, four hundred forty".