726388421 has 8 divisors (see below), whose sum is σ = 797006304. Its totient is φ = 656534320.

The previous prime is 726388391. The next prime is 726388441. The reversal of 726388421 is 124883627.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 726388421 - 2²² = 722194117 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 (726388441) 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 7 ways as a sum of consecutive naturals, for example, 188951 + ... + 192756.

It is an arithmetic number, because the mean of its divisors is an integer number (99625788).

Almost surely, 2^726388421 is an apocalyptic number.

It is an amenable number.

726388421 is a deficient number, since it is larger than the sum of its proper divisors (70617883).

726388421 is a wasteful number, since it uses less digits than its factorization.

726388421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381891.

The product of its digits is 129024, while the sum is 41.

The square root of 726388421 is about 26951.5940344908. The cubic root of 726388421 is about 898.9239902032.

The spelling of 726388421 in words is "seven hundred twenty-six million, three hundred eighty-eight thousand, four hundred twenty-one".