721876320 has 288 divisors, whose sum is σ = 2779146720. Its totient is φ = 174873600.

The previous prime is 721876313. The next prime is 721876343. The reversal of 721876320 is 23678127.

721876320 is a `hidden beast` number, since 7 + 2 + 18 + 7 + 632 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×721876320² = 1042210842753484800, which contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 522030 + ... + 523410.

It is an arithmetic number, because the mean of its divisors is an integer number (9649815).

Almost surely, 2^721876320 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 721876320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1389573360).

721876320 is an abundant number, since it is smaller than the sum of its proper divisors (2057270400).

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

721876320 is a wasteful number, since it uses less digits than its factorization.

721876320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1427 (or 1402 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 36.

The square root of 721876320 is about 26867.7561400278. The cubic root of 721876320 is about 897.0588433563.

It can be divided in two parts, 7218 and 76320, that added together give a palindrome (83538).

The spelling of 721876320 in words is "seven hundred twenty-one million, eight hundred seventy-six thousand, three hundred twenty".