721715487768 has 384 divisors, whose sum is σ = 2270319667200. Its totient is φ = 206532944640.

The previous prime is 721715487697. The next prime is 721715487769. The reversal of 721715487768 is 867784517127.

721715487768 is a `hidden beast` number, since 7 + 2 + 17 + 1 + 548 + 7 + 76 + 8 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721715487769) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1105230130 + ... + 1105230782.

It is an arithmetic number, because the mean of its divisors is an integer number (5912290800).

Almost surely, 2^721715487768 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 721715487768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1135159833600).

721715487768 is an abundant number, since it is smaller than the sum of its proper divisors (1548604179432).

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

721715487768 is a wasteful number, since it uses less digits than its factorization.

721715487768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1324 (or 1295 counting only the distinct ones).

The product of its digits is 36879360, while the sum is 63.

The spelling of 721715487768 in words is "seven hundred twenty-one billion, seven hundred fifteen million, four hundred eighty-seven thousand, seven hundred sixty-eight".