766164556081 has 8 divisors (see below), whose sum is σ = 767040117480. Its totient is φ = 765289231872.

The previous prime is 766164556067. The next prime is 766164556121. The reversal of 766164556081 is 180655461667.

It can be written as a sum of positive squares in 4 ways, for example, as 98608560400 + 667555995681 = 314020^2 + 817041^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-766164556081 is a prime.

It is a super-2 number, since 2×766164556081² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (766164356081) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6862401 + ... + 6973153.

It is an arithmetic number, because the mean of its divisors is an integer number (95880014685).

Almost surely, 2^766164556081 is an apocalyptic number.

It is an amenable number.

766164556081 is a deficient number, since it is larger than the sum of its proper divisors (875561399).

766164556081 is a wasteful number, since it uses less digits than its factorization.

766164556081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118595.

The product of its (nonzero) digits is 7257600, while the sum is 55.

The spelling of 766164556081 in words is "seven hundred sixty-six billion, one hundred sixty-four million, five hundred fifty-six thousand, eighty-one".