726404621 has 4 divisors (see below), whose sum is σ = 736635744. Its totient is φ = 716173500.

The previous prime is 726404603. The next prime is 726404647. The reversal of 726404621 is 126404627.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 126404627 = 61 ⋅2072207.

It is a cyclic number.

It is not a de Polignac number, because 726404621 - 2¹⁰ = 726403597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (726404671) 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, 5115455 + ... + 5115596.

It is an arithmetic number, because the mean of its divisors is an integer number (184158936).

Almost surely, 2^726404621 is an apocalyptic number.

726404621 is a gapful number since it is divisible by the number (71) formed by its first and last digit.

It is an amenable number.

726404621 is a deficient number, since it is larger than the sum of its proper divisors (10231123).

726404621 is a wasteful number, since it uses less digits than its factorization.

726404621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10231122.

The product of its (nonzero) digits is 16128, while the sum is 32.

The square root of 726404621 is about 26951.8945716252. The cubic root of 726404621 is about 898.9306727897.

The spelling of 726404621 in words is "seven hundred twenty-six million, four hundred four thousand, six hundred twenty-one".