716725721 has 4 divisors (see below), whose sum is σ = 717064500. Its totient is φ = 716386944.

The previous prime is 716725717. The next prime is 716725727. The reversal of 716725721 is 127527617.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 382750096 + 333975625 = 19564^2 + 18275^2 .

It is a cyclic number.

It is not a de Polignac number, because 716725721 - 2² = 716725717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (716725727) 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 3 ways as a sum of consecutive naturals, for example, 166196 + ... + 170453.

It is an arithmetic number, because the mean of its divisors is an integer number (179266125).

Almost surely, 2^716725721 is an apocalyptic number.

It is an amenable number.

716725721 is a deficient number, since it is larger than the sum of its proper divisors (338779).

716725721 is a wasteful number, since it uses less digits than its factorization.

716725721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 338778.

The product of its digits is 41160, while the sum is 38.

The square root of 716725721 is about 26771.7336196220. The cubic root of 716725721 is about 894.9202392431.

The spelling of 716725721 in words is "seven hundred sixteen million, seven hundred twenty-five thousand, seven hundred twenty-one".