78289139 has 8 divisors (see below), whose sum is σ = 82735440. Its totient is φ = 73875456.

The previous prime is 78289103. The next prime is 78289153. The reversal of 78289139 is 93198287.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78289139 - 2¹² = 78285043 is a prime.

It is a super-2 number, since 2×78289139² = 12258378570722642, 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 = 78289093 and 78289102.

It is not an unprimeable number, because it can be changed into a prime (78279139) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3134 + ... + 12899.

It is an arithmetic number, because the mean of its divisors is an integer number (10341930).

Almost surely, 2^78289139 is an apocalyptic number.

78289139 is a deficient number, since it is larger than the sum of its proper divisors (4446301).

78289139 is a wasteful number, since it uses less digits than its factorization.

78289139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16309.

The product of its digits is 217728, while the sum is 47.

The square root of 78289139 is about 8848.1149969923. The cubic root of 78289139 is about 427.7931625708.

The spelling of 78289139 in words is "seventy-eight million, two hundred eighty-nine thousand, one hundred thirty-nine".