767661 has 4 divisors (see below), whose sum is σ = 1023552. Its totient is φ = 511772.

The previous prime is 767647. The next prime is 767677. The reversal of 767661 is 166767.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 166767 = 3 ⋅55589.

It is a cyclic number.

It is not a de Polignac number, because 767661 - 2⁶ = 767597 is a prime.

It is a D-number.

It is a Curzon number.

767661 is a lucky number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 767661.

It is not an unprimeable number, because it can be changed into a prime (767681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 127941 + ... + 127946.

It is an arithmetic number, because the mean of its divisors is an integer number (255888).

2⁷⁶⁷⁶⁶¹ is an apocalyptic number.

It is an amenable number.

767661 is a deficient number, since it is larger than the sum of its proper divisors (255891).

767661 is a wasteful number, since it uses less digits than its factorization.

767661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255890.

The product of its digits is 10584, while the sum is 33.

The square root of 767661 is about 876.1626561318. The cubic root of 767661 is about 91.5636631807.

It can be divided in two parts, 76766 and 1, that added together give a palindrome (76767).

The spelling of 767661 in words is "seven hundred sixty-seven thousand, six hundred sixty-one".