78147871 has 2 divisors, whose sum is σ = 78147872. Its totient is φ = 78147870.

The previous prime is 78147863. The next prime is 78147889. The reversal of 78147871 is 17874187.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78147871 - 2³ = 78147863 is a prime.

It is a super-2 number, since 2×78147871² = 12214179483665282, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78147821) 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, 39073935 + 39073936.

It is an arithmetic number, because the mean of its divisors is an integer number (39073936).

Almost surely, 2^78147871 is an apocalyptic number.

78147871 is a deficient number, since it is larger than the sum of its proper divisors (1).

78147871 is an equidigital number, since it uses as much as digits as its factorization.

78147871 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 87808, while the sum is 43.

The square root of 78147871 is about 8840.1284492930. The cubic root of 78147871 is about 427.5356987163.

The spelling of 78147871 in words is "seventy-eight million, one hundred forty-seven thousand, eight hundred seventy-one".