766928721 has 16 divisors (see below), whose sum is σ = 1149111936. Its totient is φ = 451435776.

The previous prime is 766928707. The next prime is 766928737. The reversal of 766928721 is 127829667.

It is not a de Polignac number, because 766928721 - 2⁵ = 766928689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (766928741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 426600 + ... + 428393.

It is an arithmetic number, because the mean of its divisors is an integer number (71819496).

Almost surely, 2^766928721 is an apocalyptic number.

It is an amenable number.

766928721 is a deficient number, since it is larger than the sum of its proper divisors (382183215).

766928721 is a wasteful number, since it uses less digits than its factorization.

766928721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 855032.

The product of its digits is 508032, while the sum is 48.

The square root of 766928721 is about 27693.4779505933. The cubic root of 766928721 is about 915.3453944032.

The spelling of 766928721 in words is "seven hundred sixty-six million, nine hundred twenty-eight thousand, seven hundred twenty-one".