78669017856 has 1152 divisors, whose sum is σ = 296690688000. Its totient is φ = 20205158400.

The previous prime is 78669017839. The next prime is 78669017873. The reversal of 78669017856 is 65871096687.

It is an interprime number because it is at equal distance from previous prime (78669017839) and next prime (78669017873).

It is a tau number, because it is divible by the number of its divisors (1152).

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 78669017793 and 78669017802.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1108014301 + ... + 1108014371.

It is an arithmetic number, because the mean of its divisors is an integer number (257544000).

Almost surely, 2^78669017856 is an apocalyptic number.

78669017856 is a gapful number since it is divisible by the number (76) 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 78669017856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (148345344000).

78669017856 is an abundant number, since it is smaller than the sum of its proper divisors (218021670144).

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

78669017856 is a wasteful number, since it uses less digits than its factorization.

78669017856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198 (or 178 counting only the distinct ones).

The product of its (nonzero) digits is 30481920, while the sum is 63.

It can be divided in two parts, 786690 and 17856, that added together give a triangular number (804546 = T₁₂₆₈).

The spelling of 78669017856 in words is "seventy-eight billion, six hundred sixty-nine million, seventeen thousand, eight hundred fifty-six".