78399413 has 4 divisors (see below), whose sum is σ = 78580908. Its totient is φ = 78217920.

The previous prime is 78399401. The next prime is 78399437. The reversal of 78399413 is 31499387.

It is a happy number.

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 35129329 + 43270084 = 5927^2 + 6578^2 .

It is a cyclic number.

It is not a de Polignac number, because 78399413 - 2⁴ = 78399397 is a prime.

It is a super-2 number, since 2×78399413² = 12292935917489138, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78399473) 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, 90098 + ... + 90963.

It is an arithmetic number, because the mean of its divisors is an integer number (19645227).

Almost surely, 2^78399413 is an apocalyptic number.

It is an amenable number.

78399413 is a deficient number, since it is larger than the sum of its proper divisors (181495).

78399413 is a wasteful number, since it uses less digits than its factorization.

78399413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181494.

The product of its digits is 163296, while the sum is 44.

The square root of 78399413 is about 8854.3443009632. The cubic root of 78399413 is about 427.9939240556.

The spelling of 78399413 in words is "seventy-eight million, three hundred ninety-nine thousand, four hundred thirteen".