721505166484120 has 128 divisors (see below), whose sum is σ = 1656550961899200. Its totient is φ = 282743930880000.

The previous prime is 721505166484051. The next prime is 721505166484121. The reversal of 721505166484120 is 21484661505127.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721505166484121) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 9493326120 + ... + 9493402120.

Almost surely, 2^{721505166484120} 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 721505166484120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (828275480949600).

721505166484120 is an abundant number, since it is smaller than the sum of its proper divisors (935045795415080).

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

721505166484120 is a wasteful number, since it uses less digits than its factorization.

721505166484120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91469 (or 91465 counting only the distinct ones).

The product of its (nonzero) digits is 3225600, while the sum is 52.

The spelling of 721505166484120 in words is "seven hundred twenty-one trillion, five hundred five billion, one hundred sixty-six million, four hundred eighty-four thousand, one hundred twenty".