78787147 has 4 divisors (see below), whose sum is σ = 78829840. Its totient is φ = 78744456.

The previous prime is 78787133. The next prime is 78787157. The reversal of 78787147 is 74178787.

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 78787147 - 2⁷ = 78787019 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78787147.

It is not an unprimeable number, because it can be changed into a prime (78787127) 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, 18447 + ... + 22312.

It is an arithmetic number, because the mean of its divisors is an integer number (19707460).

Almost surely, 2^78787147 is an apocalyptic number.

78787147 is a deficient number, since it is larger than the sum of its proper divisors (42693).

78787147 is a wasteful number, since it uses less digits than its factorization.

78787147 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42692.

The product of its digits is 614656, while the sum is 49.

The square root of 78787147 is about 8876.2124242269. The cubic root of 78787147 is about 428.6983297274.

The spelling of 78787147 in words is "seventy-eight million, seven hundred eighty-seven thousand, one hundred forty-seven".