78147947 has 2 divisors, whose sum is σ = 78147948. Its totient is φ = 78147946.

The previous prime is 78147913. The next prime is 78147977. The reversal of 78147947 is 74974187.

It is a strong prime.

It is an emirp because it is prime and its reverse (74974187) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78147947 - 2¹² = 78143851 is a prime.

It is a super-2 number, since 2×78147947² = 12214203240629618, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78147907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39073973 + 39073974.

It is an arithmetic number, because the mean of its divisors is an integer number (39073974).

Almost surely, 2^78147947 is an apocalyptic number.

78147947 is a deficient number, since it is larger than the sum of its proper divisors (1).

78147947 is an equidigital number, since it uses as much as digits as its factorization.

78147947 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 395136, while the sum is 47.

The square root of 78147947 is about 8840.1327478721. The cubic root of 78147947 is about 427.5358373112.

The spelling of 78147947 in words is "seventy-eight million, one hundred forty-seven thousand, nine hundred forty-seven".