766684843861 has 4 divisors (see below), whose sum is σ = 793122252300. Its totient is φ = 740247435424.

The previous prime is 766684843843. The next prime is 766684843877. The reversal of 766684843861 is 168348486667.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 168348486667 = 1583 ⋅106347749.

It can be written as a sum of positive squares in 2 ways, for example, as 439146107761 + 327538736100 = 662681^2 + 572310^2 .

It is a cyclic number.

It is not a de Polignac number, because 766684843861 - 2⁵ = 766684843829 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (766684840861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13218704176 + ... + 13218704233.

It is an arithmetic number, because the mean of its divisors is an integer number (198280563075).

Almost surely, 2^766684843861 is an apocalyptic number.

It is an amenable number.

766684843861 is a deficient number, since it is larger than the sum of its proper divisors (26437408439).

766684843861 is a wasteful number, since it uses less digits than its factorization.

766684843861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26437408438.

The product of its digits is 222953472, while the sum is 67.

The spelling of 766684843861 in words is "seven hundred sixty-six billion, six hundred eighty-four million, eight hundred forty-three thousand, eight hundred sixty-one".