78644945808 has 120 divisors (see below), whose sum is σ = 258575116800. Its totient is φ = 21998580480.

The previous prime is 78644945801. The next prime is 78644945839. The reversal of 78644945808 is 80854944687.

78644945808 is a `hidden beast` number, since 7 + 8 + 6 + 4 + 49 + 4 + 580 + 8 = 666.

It is a super-2 number, since 2×78644945808² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78644945801) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 1889008 + ... + 1930191.

It is an arithmetic number, because the mean of its divisors is an integer number (2154792640).

Almost surely, 2^78644945808 is an apocalyptic number.

78644945808 is a gapful number since it is divisible by the number (78) formed by its first and last digit.

It is an amenable number.

78644945808 is an abundant number, since it is smaller than the sum of its proper divisors (179930170992).

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

78644945808 is a wasteful number, since it uses less digits than its factorization.

78644945808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3819237 (or 3819228 counting only the distinct ones).

The product of its (nonzero) digits is 61931520, while the sum is 63.

The spelling of 78644945808 in words is "seventy-eight billion, six hundred forty-four million, nine hundred forty-five thousand, eight hundred eight".