6819782561 has 2 divisors, whose sum is σ = 6819782562. Its totient is φ = 6819782560.

The previous prime is 6819782551. The next prime is 6819782569. The reversal of 6819782561 is 1652879186.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5278749025 + 1541033536 = 72655^2 + 39256^2 .

It is a cyclic number.

It is not a de Polignac number, because 6819782561 - 2¹⁸ = 6819520417 is a prime.

It is not a weakly prime, because it can be changed into another prime (6819782569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3409891280 + 3409891281.

It is an arithmetic number, because the mean of its divisors is an integer number (3409891281).

Almost surely, 2^6819782561 is an apocalyptic number.

It is an amenable number.

6819782561 is a deficient number, since it is larger than the sum of its proper divisors (1).

6819782561 is an equidigital number, since it uses as much as digits as its factorization.

6819782561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1451520, while the sum is 53.

The square root of 6819782561 is about 82581.9747947456. The cubic root of 6819782561 is about 1896.3718909194.

The spelling of 6819782561 in words is "six billion, eight hundred nineteen million, seven hundred eighty-two thousand, five hundred sixty-one".