78628913 has 8 divisors (see below), whose sum is σ = 85875456. Its totient is φ = 71398800.

The previous prime is 78628909. The next prime is 78628931. The reversal of 78628913 is 31982687.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 78628913 - 2² = 78628909 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78628013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7295 + ... + 14507.

It is an arithmetic number, because the mean of its divisors is an integer number (10734432).

Almost surely, 2^78628913 is an apocalyptic number.

It is an amenable number.

78628913 is a deficient number, since it is larger than the sum of its proper divisors (7246543).

78628913 is a wasteful number, since it uses less digits than its factorization.

78628913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8215.

The product of its digits is 145152, while the sum is 44.

The square root of 78628913 is about 8867.2945704989. The cubic root of 78628913 is about 428.4111419594.

The spelling of 78628913 in words is "seventy-eight million, six hundred twenty-eight thousand, nine hundred thirteen".