78617897 has 2 divisors, whose sum is σ = 78617898. Its totient is φ = 78617896.

The previous prime is 78617879. The next prime is 78617923. The reversal of 78617897 is 79871687.

Together with previous prime (78617879) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73685056 + 4932841 = 8584^2 + 2221^2 .

It is a cyclic number.

It is not a de Polignac number, because 78617897 - 2⁸ = 78617641 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78617807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39308948 + 39308949.

It is an arithmetic number, because the mean of its divisors is an integer number (39308949).

Almost surely, 2^78617897 is an apocalyptic number.

It is an amenable number.

78617897 is a deficient number, since it is larger than the sum of its proper divisors (1).

78617897 is an equidigital number, since it uses as much as digits as its factorization.

78617897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1185408, while the sum is 53.

The square root of 78617897 is about 8866.6733897218. The cubic root of 78617897 is about 428.3911340625.

The spelling of 78617897 in words is "seventy-eight million, six hundred seventeen thousand, eight hundred ninety-seven".