766634343413321 has 4 divisors (see below), whose sum is σ = 766634413982100. Its totient is φ = 766634272844544.

The previous prime is 766634343413311. The next prime is 766634343413329. The reversal of 766634343413321 is 123314343436667.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 521459375185225 + 245174968228096 = 22835485^2 + 15658064^2 .

It is a cyclic number.

It is not a de Polignac number, because 766634343413321 - 2³⁴ = 766617163544137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (766634343413329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15164756 + ... + 41990933.

It is an arithmetic number, because the mean of its divisors is an integer number (191658603495525).

Almost surely, 2^{766634343413321} is an apocalyptic number.

It is an amenable number.

766634343413321 is a deficient number, since it is larger than the sum of its proper divisors (70568779).

766634343413321 is a wasteful number, since it uses less digits than its factorization.

766634343413321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70568778.

The product of its digits is 47029248, while the sum is 56.

Adding to 766634343413321 its reverse (123314343436667), we get a palindrome (889948686849988).

The spelling of 766634343413321 in words is "seven hundred sixty-six trillion, six hundred thirty-four billion, three hundred forty-three million, four hundred thirteen thousand, three hundred twenty-one".