78105683658564 has 81 divisors (see below), whose sum is σ = 198295525938783. Its totient is φ = 25922087113104.

The previous prime is 78105683658557. The next prime is 78105683658581. The reversal of 78105683658564 is 46585638650187.

The square root of 78105683658564 is 8837742.

It is a perfect power (a square), and thus also a powerful number.

78105683658564 is a `hidden beast` number, since 7 + 8 + 1 + 0 + 5 + 6 + 8 + 3 + 6 + 58 + 564 = 666.

It is a super-2 number, since 2×78105683658564² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78105683658492 and 78105683658501.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 12673318947 + ... + 12673325109.

Almost surely, 2^{78105683658564} is an apocalyptic number.

78105683658564 is the 8837742-nd square number.

It is an amenable number.

78105683658564 is an abundant number, since it is smaller than the sum of its proper divisors (120189842280219).

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

78105683658564 is an frugal number, since it uses more digits than its factorization.

78105683658564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12814 (or 6407 counting only the distinct ones).

The product of its (nonzero) digits is 1161216000, while the sum is 72.

The spelling of 78105683658564 in words is "seventy-eight trillion, one hundred five billion, six hundred eighty-three million, six hundred fifty-eight thousand, five hundred sixty-four".