78688512 has 324 divisors, whose sum is σ = 286260156. Its totient is φ = 20643840.

The previous prime is 78688507. The next prime is 78688537. The reversal of 78688512 is 21588687.

78688512 is a `hidden beast` number, since 78 + 68 + 8 + 512 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 28901376 + 49787136 = 5376^2 + 7056^2 .

Its product of digits (215040) is a multiple of the sum of its prime divisors (70).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1919212 + ... + 1919252.

It is an arithmetic number, because the mean of its divisors is an integer number (883519).

Almost surely, 2^78688512 is an apocalyptic number.

78688512 is a gapful number since it is divisible by the number (72) 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 78688512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143130078).

78688512 is an abundant number, since it is smaller than the sum of its proper divisors (207571644).

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

78688512 is a wasteful number, since it uses less digits than its factorization.

78688512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94 (or 70 counting only the distinct ones).

The product of its digits is 215040, while the sum is 45.

The square root of 78688512 is about 8870.6545418024. The cubic root of 78688512 is about 428.5193567211.

It can be divided in two parts, 786 and 88512, that added together give a palindrome (89298).

The spelling of 78688512 in words is "seventy-eight million, six hundred eighty-eight thousand, five hundred twelve".