78855565824 has 400 divisors, whose sum is σ = 275285469888. Its totient is φ = 22002720768.

The previous prime is 78855565819. The next prime is 78855565829. The reversal of 78855565824 is 42856555887.

It is a happy number.

78855565824 is a `hidden beast` number, since 7 + 8 + 8 + 5 + 556 + 58 + 24 = 666.

It is an interprime number because it is at equal distance from previous prime (78855565819) and next prime (78855565829).

It is a super-2 number, since 2×78855565824² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (78855565829) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 12479914 + ... + 12486230.

Almost surely, 2^78855565824 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 78855565824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137642734944).

78855565824 is an abundant number, since it is smaller than the sum of its proper divisors (196429904064).

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

78855565824 is an equidigital number, since it uses as much as digits as its factorization.

78855565824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6397 (or 6372 counting only the distinct ones).

The product of its digits is 107520000, while the sum is 63.

The spelling of 78855565824 in words is "seventy-eight billion, eight hundred fifty-five million, five hundred sixty-five thousand, eight hundred twenty-four".