6346720078661 has 2 divisors, whose sum is σ = 6346720078662. Its totient is φ = 6346720078660.

The previous prime is 6346720078631. The next prime is 6346720078679. The reversal of 6346720078661 is 1668700276436.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6277705636225 + 69014442436 = 2505535^2 + 262706^2 .

It is a cyclic number.

It is not a de Polignac number, because 6346720078661 - 2⁴² = 1948673567557 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 6346720078597 and 6346720078606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6346720078631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3173360039330 + 3173360039331.

It is an arithmetic number, because the mean of its divisors is an integer number (3173360039331).

Almost surely, 2^{6346720078661} is an apocalyptic number.

It is an amenable number.

6346720078661 is a deficient number, since it is larger than the sum of its proper divisors (1).

6346720078661 is an equidigital number, since it uses as much as digits as its factorization.

6346720078661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12192768, while the sum is 56.

The spelling of 6346720078661 in words is "six trillion, three hundred forty-six billion, seven hundred twenty million, seventy-eight thousand, six hundred sixty-one".