766408616881 has 2 divisors, whose sum is σ = 766408616882. Its totient is φ = 766408616880.

The previous prime is 766408616807. The next prime is 766408616887. The reversal of 766408616881 is 188616804667.

766408616881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 597968144656 + 168440472225 = 773284^2 + 410415^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-766408616881 is a prime.

It is a super-2 number, since 2×766408616881² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (766408616887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 383204308440 + 383204308441.

It is an arithmetic number, because the mean of its divisors is an integer number (383204308441).

Almost surely, 2^766408616881 is an apocalyptic number.

It is an amenable number.

766408616881 is a deficient number, since it is larger than the sum of its proper divisors (1).

766408616881 is an equidigital number, since it uses as much as digits as its factorization.

766408616881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18579456, while the sum is 61.

The spelling of 766408616881 in words is "seven hundred sixty-six billion, four hundred eight million, six hundred sixteen thousand, eight hundred eighty-one".