78964139 has 2 divisors, whose sum is σ = 78964140. Its totient is φ = 78964138.

The previous prime is 78964121. The next prime is 78964153. The reversal of 78964139 is 93146987.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78964139 - 2¹² = 78960043 is a prime.

It is a super-2 number, since 2×78964139² = 12470670496022642, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 78964093 and 78964102.

It is not a weakly prime, because it can be changed into another prime (78964159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39482069 + 39482070.

It is an arithmetic number, because the mean of its divisors is an integer number (39482070).

Almost surely, 2^78964139 is an apocalyptic number.

78964139 is a deficient number, since it is larger than the sum of its proper divisors (1).

78964139 is an equidigital number, since it uses as much as digits as its factorization.

78964139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 326592, while the sum is 47.

The square root of 78964139 is about 8886.1768494668. The cubic root of 78964139 is about 429.0191072100.

The spelling of 78964139 in words is "seventy-eight million, nine hundred sixty-four thousand, one hundred thirty-nine".