716521 has 4 divisors (see below), whose sum is σ = 771652. Its totient is φ = 661392.

The previous prime is 716501. The next prime is 716531. The reversal of 716521 is 125617.

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 440896 + 275625 = 664^2 + 525^2 .

It is a cyclic number.

It is not a de Polignac number, because 716521 - 2¹³ = 708329 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 716492 and 716501.

It is not an unprimeable number, because it can be changed into a prime (716501) 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, 27546 + ... + 27571.

It is an arithmetic number, because the mean of its divisors is an integer number (192913).

2⁷¹⁶⁵²¹ is an apocalyptic number.

It is an amenable number.

716521 is a deficient number, since it is larger than the sum of its proper divisors (55131).

716521 is a wasteful number, since it uses less digits than its factorization.

716521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55130.

The product of its digits is 420, while the sum is 22.

The square root of 716521 is about 846.4756346169. The cubic root of 716521 is about 89.4835024678.

The spelling of 716521 in words is "seven hundred sixteen thousand, five hundred twenty-one".