78684313 has 4 divisors (see below), whose sum is σ = 83312820. Its totient is φ = 74055808.

The previous prime is 78684299. The next prime is 78684349. The reversal of 78684313 is 31348687.

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

It can be written as a sum of positive squares in 2 ways, for example, as 28174864 + 50509449 = 5308^2 + 7107^2 .

It is not a de Polignac number, because 78684313 - 2¹³ = 78676121 is a prime.

It is a super-2 number, since 2×78684313² = 12382442224563938, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78684373) 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, 2314228 + ... + 2314261.

It is an arithmetic number, because the mean of its divisors is an integer number (20828205).

Almost surely, 2^78684313 is an apocalyptic number.

It is an amenable number.

78684313 is a deficient number, since it is larger than the sum of its proper divisors (4628507).

78684313 is a wasteful number, since it uses less digits than its factorization.

78684313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4628506.

The product of its digits is 96768, while the sum is 40.

The square root of 78684313 is about 8870.4178593796. The cubic root of 78684313 is about 428.5117343260.

The spelling of 78684313 in words is "seventy-eight million, six hundred eighty-four thousand, three hundred thirteen".