78787847 has 4 divisors (see below), whose sum is σ = 78807456. Its totient is φ = 78768240.

The previous prime is 78787831. The next prime is 78787853. The reversal of 78787847 is 74878787.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 78787847 - 2⁴ = 78787831 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78787792 and 78787801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78787817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1343 + ... + 12624.

It is an arithmetic number, because the mean of its divisors is an integer number (19701864).

Almost surely, 2^78787847 is an apocalyptic number.

78787847 is a deficient number, since it is larger than the sum of its proper divisors (19609).

78787847 is a wasteful number, since it uses less digits than its factorization.

78787847 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19608.

The product of its digits is 4917248, while the sum is 56.

The square root of 78787847 is about 8876.2518553723. The cubic root of 78787847 is about 428.6995993420.

The spelling of 78787847 in words is "seventy-eight million, seven hundred eighty-seven thousand, eight hundred forty-seven".