78385039 has 4 divisors (see below), whose sum is σ = 79864056. Its totient is φ = 76906024.

The previous prime is 78385033. The next prime is 78385093. The reversal of 78385039 is 93058387.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93058387 = 1117 ⋅83311.

It is a cyclic number.

It is not a de Polignac number, because 78385039 - 2³ = 78385031 is a prime.

It is a super-2 number, since 2×78385039² = 12288428678063042, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78384986 and 78385004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78385031) 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, 739429 + ... + 739534.

It is an arithmetic number, because the mean of its divisors is an integer number (19966014).

Almost surely, 2^78385039 is an apocalyptic number.

78385039 is a deficient number, since it is larger than the sum of its proper divisors (1479017).

78385039 is a wasteful number, since it uses less digits than its factorization.

78385039 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1479016.

The product of its (nonzero) digits is 181440, while the sum is 43.

The square root of 78385039 is about 8853.5325718043. The cubic root of 78385039 is about 427.9677658637.

The spelling of 78385039 in words is "seventy-eight million, three hundred eighty-five thousand, thirty-nine".