721318752 has 216 divisors, whose sum is σ = 2577648528. Its totient is φ = 187292160.

The previous prime is 721318751. The next prime is 721318853. The reversal of 721318752 is 257813127.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721318751) 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 35 ways as a sum of consecutive naturals, for example, 242458 + ... + 245414.

It is an arithmetic number, because the mean of its divisors is an integer number (11933558).

Almost surely, 2^721318752 is an apocalyptic number.

721318752 is a gapful number since it is divisible by the number (72) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 721318752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1288824264).

721318752 is an abundant number, since it is smaller than the sum of its proper divisors (1856329776).

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

721318752 is a wasteful number, since it uses less digits than its factorization.

721318752 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3002 (or 2980 counting only the distinct ones).

The product of its digits is 23520, while the sum is 36.

The square root of 721318752 is about 26857.3779807337. The cubic root of 721318752 is about 896.8278249570.

The spelling of 721318752 in words is "seven hundred twenty-one million, three hundred eighteen thousand, seven hundred fifty-two".