678568585865909 has 2 divisors, whose sum is σ = 678568585865910. Its totient is φ = 678568585865908.

The previous prime is 678568585865873. The next prime is 678568585865917. The reversal of 678568585865909 is 909568585865876.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 609071303596900 + 69497282269009 = 24679370^2 + 8336503^2 .

It is a cyclic number.

It is not a de Polignac number, because 678568585865909 - 2¹² = 678568585861813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (678568585865969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339284292932954 + 339284292932955.

It is an arithmetic number, because the mean of its divisors is an integer number (339284292932955).

Almost surely, 2^{678568585865909} is an apocalyptic number.

It is an amenable number.

678568585865909 is a deficient number, since it is larger than the sum of its proper divisors (1).

678568585865909 is an equidigital number, since it uses as much as digits as its factorization.

678568585865909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 313528320000, while the sum is 95.

The spelling of 678568585865909 in words is "six hundred seventy-eight trillion, five hundred sixty-eight billion, five hundred eighty-five million, eight hundred sixty-five thousand, nine hundred nine".