78647760 has 200 divisors, whose sum is σ = 279524520. Its totient is φ = 20487168.

The previous prime is 78647759. The next prime is 78647761. The reversal of 78647760 is 6774687.

It is an interprime number because it is at equal distance from previous prime (78647759) and next prime (78647761).

It can be written as a sum of positive squares in 4 ways, for example, as 32353344 + 46294416 = 5688^2 + 6804^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78647761) 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, 343326 + ... + 343554.

Almost surely, 2^78647760 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 78647760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (139762260).

78647760 is an abundant number, since it is smaller than the sum of its proper divisors (200876760).

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

78647760 is a wasteful number, since it uses less digits than its factorization.

78647760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307 (or 292 counting only the distinct ones).

The product of its (nonzero) digits is 395136, while the sum is 45.

The square root of 78647760 is about 8868.3572323176. The cubic root of 78647760 is about 428.4453686387.

The spelling of 78647760 in words is "seventy-eight million, six hundred forty-seven thousand, seven hundred sixty".