726645421 has 2 divisors, whose sum is σ = 726645422. Its totient is φ = 726645420.

The previous prime is 726645389. The next prime is 726645461. The reversal of 726645421 is 124546627.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 474629796 + 252015625 = 21786^2 + 15875^2 .

It is a cyclic number.

It is not a de Polignac number, because 726645421 - 2⁵ = 726645389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (726645461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 363322710 + 363322711.

It is an arithmetic number, because the mean of its divisors is an integer number (363322711).

Almost surely, 2^726645421 is an apocalyptic number.

It is an amenable number.

726645421 is a deficient number, since it is larger than the sum of its proper divisors (1).

726645421 is an equidigital number, since it uses as much as digits as its factorization.

726645421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 80640, while the sum is 37.

The square root of 726645421 is about 26956.3614198949. The cubic root of 726645421 is about 899.0299923632.

The spelling of 726645421 in words is "seven hundred twenty-six million, six hundred forty-five thousand, four hundred twenty-one".