78947139 has 4 divisors (see below), whose sum is σ = 105262856. Its totient is φ = 52631424.

The previous prime is 78947119. The next prime is 78947153. The reversal of 78947139 is 93174987.

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

It is not a de Polignac number, because 78947139 - 2⁵ = 78947107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78947119) 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, 13157854 + ... + 13157859.

It is an arithmetic number, because the mean of its divisors is an integer number (26315714).

Almost surely, 2^78947139 is an apocalyptic number.

78947139 is a deficient number, since it is larger than the sum of its proper divisors (26315717).

78947139 is a wasteful number, since it uses less digits than its factorization.

78947139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26315716.

The product of its digits is 381024, while the sum is 48.

The square root of 78947139 is about 8885.2202561332. The cubic root of 78947139 is about 428.9883175024.

The spelling of 78947139 in words is "seventy-eight million, nine hundred forty-seven thousand, one hundred thirty-nine".