726563621 has 6 divisors (see below), whose sum is σ = 845186310. Its totient is φ = 622768776.

The previous prime is 726563609. The next prime is 726563623. The reversal of 726563621 is 126365627.

It can be written as a sum of positive squares in only one way, i.e., 726302500 + 261121 = 26950^2 + 511^2 .

It is not a de Polignac number, because 726563621 - 2⁶ = 726563557 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (726563623) 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 5 ways as a sum of consecutive naturals, for example, 7413866 + ... + 7413963.

It is an arithmetic number, because the mean of its divisors is an integer number (140864385).

Almost surely, 2^726563621 is an apocalyptic number.

It is an amenable number.

726563621 is a deficient number, since it is larger than the sum of its proper divisors (118622689).

726563621 is a wasteful number, since it uses less digits than its factorization.

726563621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14827843 (or 14827836 counting only the distinct ones).

The product of its digits is 90720, while the sum is 38.

The square root of 726563621 is about 26954.8441101038. The cubic root of 726563621 is about 898.9962558663.

The spelling of 726563621 in words is "seven hundred twenty-six million, five hundred sixty-three thousand, six hundred twenty-one".