726521 has 2 divisors, whose sum is σ = 726522. Its totient is φ = 726520.

The previous prime is 726497. The next prime is 726527. The reversal of 726521 is 125627.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 511225 + 215296 = 715^2 + 464^2 .

It is an emirp because it is prime and its reverse (125627) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 726521 - 2⁶ = 726457 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (726527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 363260 + 363261.

It is an arithmetic number, because the mean of its divisors is an integer number (363261).

2⁷²⁶⁵²¹ is an apocalyptic number.

It is an amenable number.

726521 is a deficient number, since it is larger than the sum of its proper divisors (1).

726521 is an equidigital number, since it uses as much as digits as its factorization.

726521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 840, while the sum is 23.

The square root of 726521 is about 852.3620122929. The cubic root of 726521 is about 89.8978676828.

The spelling of 726521 in words is "seven hundred twenty-six thousand, five hundred twenty-one".