78986647 has 4 divisors (see below), whose sum is σ = 79256520. Its totient is φ = 78716776.

The previous prime is 78986639. The next prime is 78986659. The reversal of 78986647 is 74668987.

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 78986647 - 2³ = 78986639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78986147) 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, 134497 + ... + 135082.

It is an arithmetic number, because the mean of its divisors is an integer number (19814130).

Almost surely, 2^78986647 is an apocalyptic number.

78986647 is a deficient number, since it is larger than the sum of its proper divisors (269873).

78986647 is a wasteful number, since it uses less digits than its factorization.

78986647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269872.

The product of its digits is 4064256, while the sum is 55.

The square root of 78986647 is about 8887.4432206344. The cubic root of 78986647 is about 429.0598659850.

The spelling of 78986647 in words is "seventy-eight million, nine hundred eighty-six thousand, six hundred forty-seven".