78382139 has 4 divisors (see below), whose sum is σ = 85507800. Its totient is φ = 71256480.

The previous prime is 78382081. The next prime is 78382151. The reversal of 78382139 is 93128387.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78382139 is a prime.

It is a super-2 number, since 2×78382139² = 12287519428430642, 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 = 78382096 and 78382105.

It is not an unprimeable number, because it can be changed into a prime (78382039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3562814 + ... + 3562835.

It is an arithmetic number, because the mean of its divisors is an integer number (21376950).

Almost surely, 2^78382139 is an apocalyptic number.

78382139 is a deficient number, since it is larger than the sum of its proper divisors (7125661).

78382139 is a wasteful number, since it uses less digits than its factorization.

78382139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7125660.

The product of its digits is 72576, while the sum is 41.

The square root of 78382139 is about 8853.3687938547. The cubic root of 78382139 is about 427.9624879780.

The spelling of 78382139 in words is "seventy-eight million, three hundred eighty-two thousand, one hundred thirty-nine".