765704721 has 4 divisors (see below), whose sum is σ = 1020939632. Its totient is φ = 510469812.

The previous prime is 765704699. The next prime is 765704749. The reversal of 765704721 is 127407567.

765704721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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.

It is not a de Polignac number, because 765704721 - 2⁵ = 765704689 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 765704721.

It is not an unprimeable number, because it can be changed into a prime (765704791) 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, 127617451 + ... + 127617456.

It is an arithmetic number, because the mean of its divisors is an integer number (255234908).

Almost surely, 2^765704721 is an apocalyptic number.

It is an amenable number.

765704721 is a deficient number, since it is larger than the sum of its proper divisors (255234911).

765704721 is a wasteful number, since it uses less digits than its factorization.

765704721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255234910.

The product of its (nonzero) digits is 82320, while the sum is 39.

The square root of 765704721 is about 27671.3700600458. The cubic root of 765704721 is about 914.8581786226.

The spelling of 765704721 in words is "seven hundred sixty-five million, seven hundred four thousand, seven hundred twenty-one".