766691 has 4 divisors (see below), whose sum is σ = 774384. Its totient is φ = 759000.

The previous prime is 766687. The next prime is 766721. The reversal of 766691 is 196667.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 196667 = 193 ⋅1019.

It is a cyclic number.

It is not a de Polignac number, because 766691 - 2² = 766687 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (766651) 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, 3695 + ... + 3896.

It is an arithmetic number, because the mean of its divisors is an integer number (193596).

2⁷⁶⁶⁶⁹¹ is an apocalyptic number.

766691 is a deficient number, since it is larger than the sum of its proper divisors (7693).

766691 is a wasteful number, since it uses less digits than its factorization.

766691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7692.

The product of its digits is 13608, while the sum is 35.

The square root of 766691 is about 875.6089309732. The cubic root of 766691 is about 91.5250809642.

The spelling of 766691 in words is "seven hundred sixty-six thousand, six hundred ninety-one".