721665462 has 64 divisors (see below), whose sum is σ = 1687795200. Its totient is φ = 201450240.

The previous prime is 721665433. The next prime is 721665463. The reversal of 721665462 is 264566127.

It is a self number, because there is not a number n which added to its sum of digits gives 721665462.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721665463) 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 31 ways as a sum of consecutive naturals, for example, 447714 + ... + 449322.

It is an arithmetic number, because the mean of its divisors is an integer number (26371800).

Almost surely, 2^721665462 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 721665462, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (843897600).

721665462 is an abundant number, since it is smaller than the sum of its proper divisors (966129738).

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

721665462 is a wasteful number, since it uses less digits than its factorization.

721665462 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1861.

The product of its digits is 120960, while the sum is 39.

The square root of 721665462 is about 26863.8318562338. The cubic root of 721665462 is about 896.9714920800.

The spelling of 721665462 in words is "seven hundred twenty-one million, six hundred sixty-five thousand, four hundred sixty-two".