721313340 has 192 divisors, whose sum is σ = 2347107840. Its totient is φ = 163676160.

The previous prime is 721313339. The next prime is 721313377. The reversal of 721313340 is 43313127.

It is a self number, because there is not a number n which added to its sum of digits gives 721313340.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1216084 + ... + 1216676.

It is an arithmetic number, because the mean of its divisors is an integer number (12224520).

Almost surely, 2^721313340 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 721313340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1173553920).

721313340 is an abundant number, since it is smaller than the sum of its proper divisors (1625794500).

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

721313340 is a wasteful number, since it uses less digits than its factorization.

721313340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 732 (or 730 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 24.

The square root of 721313340 is about 26857.2772261076. The cubic root of 721313340 is about 896.8255820076.

Adding to 721313340 its reverse (43313127), we get a palindrome (764626467).

The spelling of 721313340 in words is "seven hundred twenty-one million, three hundred thirteen thousand, three hundred forty".