6699565619381 has 2 divisors, whose sum is σ = 6699565619382. Its totient is φ = 6699565619380.

The previous prime is 6699565619363. The next prime is 6699565619419. The reversal of 6699565619381 is 1839165659966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5695100646481 + 1004464972900 = 2386441^2 + 1002230^2 .

It is a cyclic number.

It is not a de Polignac number, because 6699565619381 - 2²⁶ = 6699498510517 is a prime.

It is a super-2 number, since 2×6699565619381² (a number of 26 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 6699565619299 and 6699565619308.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6699565619081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3349782809690 + 3349782809691.

It is an arithmetic number, because the mean of its divisors is an integer number (3349782809691).

Almost surely, 2^{6699565619381} is an apocalyptic number.

It is an amenable number.

6699565619381 is a deficient number, since it is larger than the sum of its proper divisors (1).

6699565619381 is an equidigital number, since it uses as much as digits as its factorization.

6699565619381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 566870400, while the sum is 74.

The spelling of 6699565619381 in words is "six trillion, six hundred ninety-nine billion, five hundred sixty-five million, six hundred nineteen thousand, three hundred eighty-one".