726221 has 2 divisors, whose sum is σ = 726222. Its totient is φ = 726220.

The previous prime is 726191. The next prime is 726287. The reversal of 726221 is 122627.

726221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 722500 + 3721 = 850^2 + 61^2 .

It is a cyclic number.

It is not a de Polignac number, because 726221 - 2⁶ = 726157 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 726193 and 726202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (726521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 363110 + 363111.

It is an arithmetic number, because the mean of its divisors is an integer number (363111).

2⁷²⁶²²¹ is an apocalyptic number.

It is an amenable number.

726221 is a deficient number, since it is larger than the sum of its proper divisors (1).

726221 is an equidigital number, since it uses as much as digits as its factorization.

726221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 336, while the sum is 20.

The square root of 726221 is about 852.1860125583. The cubic root of 726221 is about 89.8854922327.

Adding to 726221 its reverse (122627), we get a palindrome (848848).

The spelling of 726221 in words is "seven hundred twenty-six thousand, two hundred twenty-one".