726649664 has 112 divisors (see below), whose sum is σ = 1605320640. Its totient is φ = 324280320.

The previous prime is 726649621. The next prime is 726649687. The reversal of 726649664 is 466946627.

It is a happy number.

726649664 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5546879 + ... + 5547009.

It is an arithmetic number, because the mean of its divisors is an integer number (14333220).

Almost surely, 2^726649664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 726649664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (802660320).

726649664 is an abundant number, since it is smaller than the sum of its proper divisors (878670976).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

726649664 is a wasteful number, since it uses less digits than its factorization.

726649664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 328 (or 318 counting only the distinct ones).

The product of its digits is 2612736, while the sum is 50.

The square root of 726649664 is about 26956.4401210546. The cubic root of 726649664 is about 899.0317422203.

It can be divided in two parts, 72664 and 9664, that added together give a palindrome (82328).

The spelling of 726649664 in words is "seven hundred twenty-six million, six hundred forty-nine thousand, six hundred sixty-four".