766461251665 has 4 divisors (see below), whose sum is σ = 919753502004. Its totient is φ = 613169001328.

The previous prime is 766461251627. The next prime is 766461251669. The reversal of 766461251665 is 566152164667.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 154776149056 + 611685102609 = 393416^2 + 782103^2 .

It is a cyclic number.

It is not a de Polignac number, because 766461251665 - 2³⁹ = 216705437777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (766461251669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 76646125162 + ... + 76646125171.

It is an arithmetic number, because the mean of its divisors is an integer number (229938375501).

Almost surely, 2^766461251665 is an apocalyptic number.

It is an amenable number.

766461251665 is a deficient number, since it is larger than the sum of its proper divisors (153292250339).

766461251665 is a wasteful number, since it uses less digits than its factorization.

766461251665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153292250338.

The product of its digits is 10886400, while the sum is 55.

The spelling of 766461251665 in words is "seven hundred sixty-six billion, four hundred sixty-one million, two hundred fifty-one thousand, six hundred sixty-five".