7766647821749 has 2 divisors, whose sum is σ = 7766647821750. Its totient is φ = 7766647821748.

The previous prime is 7766647821743. The next prime is 7766647821763. The reversal of 7766647821749 is 9471287466677.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7708496910724 + 58150911025 = 2776418^2 + 241145^2 .

It is an emirp because it is prime and its reverse (9471287466677) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7766647821749 - 2²⁴ = 7766631044533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7766647821743) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3883323910874 + 3883323910875.

It is an arithmetic number, because the mean of its divisors is an integer number (3883323910875).

Almost surely, 2^{7766647821749} is an apocalyptic number.

It is an amenable number.

7766647821749 is a deficient number, since it is larger than the sum of its proper divisors (1).

7766647821749 is an equidigital number, since it uses as much as digits as its factorization.

7766647821749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1194891264, while the sum is 74.

The spelling of 7766647821749 in words is "seven trillion, seven hundred sixty-six billion, six hundred forty-seven million, eight hundred twenty-one thousand, seven hundred forty-nine".