6809219861 has 2 divisors, whose sum is σ = 6809219862. Its totient is φ = 6809219860.

The previous prime is 6809219777. The next prime is 6809219869. The reversal of 6809219861 is 1689129086.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4343600836 + 2465619025 = 65906^2 + 49655^2 .

It is a cyclic number.

It is not a de Polignac number, because 6809219861 - 2¹⁰ = 6809218837 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6809219869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3404609930 + 3404609931.

It is an arithmetic number, because the mean of its divisors is an integer number (3404609931).

Almost surely, 2^6809219861 is an apocalyptic number.

It is an amenable number.

6809219861 is a deficient number, since it is larger than the sum of its proper divisors (1).

6809219861 is an equidigital number, since it uses as much as digits as its factorization.

6809219861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 373248, while the sum is 50.

The square root of 6809219861 is about 82517.9971945514. The cubic root of 6809219861 is about 1895.3923309625.

The spelling of 6809219861 in words is "six billion, eight hundred nine million, two hundred nineteen thousand, eight hundred sixty-one".