78315619 has 4 divisors (see below), whose sum is σ = 78336496. Its totient is φ = 78294744.

The previous prime is 78315613. The next prime is 78315647. The reversal of 78315619 is 91651387.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 91651387 = 271 ⋅338197.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78315619 is a prime.

It is a super-2 number, since 2×78315619² = 12266672358706322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78315613) 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, 3084 + ... + 12889.

It is an arithmetic number, because the mean of its divisors is an integer number (19584124).

Almost surely, 2^78315619 is an apocalyptic number.

78315619 is a deficient number, since it is larger than the sum of its proper divisors (20877).

78315619 is a wasteful number, since it uses less digits than its factorization.

78315619 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20876.

The product of its digits is 45360, while the sum is 40.

The square root of 78315619 is about 8849.6112343989. The cubic root of 78315619 is about 427.8413884429.

The spelling of 78315619 in words is "seventy-eight million, three hundred fifteen thousand, six hundred nineteen".