6685878413 has 2 divisors, whose sum is σ = 6685878414. Its totient is φ = 6685878412.

The previous prime is 6685878391. The next prime is 6685878427. The reversal of 6685878413 is 3148785866.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3374796649 + 3311081764 = 58093^2 + 57542^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6685878413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6685878013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3342939206 + 3342939207.

It is an arithmetic number, because the mean of its divisors is an integer number (3342939207).

Almost surely, 2^6685878413 is an apocalyptic number.

It is an amenable number.

6685878413 is a deficient number, since it is larger than the sum of its proper divisors (1).

6685878413 is an equidigital number, since it uses as much as digits as its factorization.

6685878413 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7741440, while the sum is 56.

The square root of 6685878413 is about 81767.2208956621. The cubic root of 6685878413 is about 1883.8782184442.

The spelling of 6685878413 in words is "six billion, six hundred eighty-five million, eight hundred seventy-eight thousand, four hundred thirteen".