78159139 has 2 divisors, whose sum is σ = 78159140. Its totient is φ = 78159138.

The previous prime is 78159127. The next prime is 78159187. The reversal of 78159139 is 93195187.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78159139 - 2¹¹ = 78157091 is a prime.

It is a super-2 number, since 2×78159139² = 12217702018442642, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78159095 and 78159104.

It is not a weakly prime, because it can be changed into another prime (78159119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39079569 + 39079570.

It is an arithmetic number, because the mean of its divisors is an integer number (39079570).

Almost surely, 2^78159139 is an apocalyptic number.

78159139 is a deficient number, since it is larger than the sum of its proper divisors (1).

78159139 is an equidigital number, since it uses as much as digits as its factorization.

78159139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 68040, while the sum is 43.

The square root of 78159139 is about 8840.7657473773. The cubic root of 78159139 is about 427.5562462614.

The spelling of 78159139 in words is "seventy-eight million, one hundred fifty-nine thousand, one hundred thirty-nine".