581720520961 has 8 divisors (see below), whose sum is σ = 606518277120. Its totient is φ = 557238660048.

The previous prime is 581720520959. The next prime is 581720520989. The reversal of 581720520961 is 169025027185.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 581720520961 - 2¹ = 581720520959 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (581720520061) 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 7 ways as a sum of consecutive naturals, for example, 78970051 + ... + 78977416.

It is an arithmetic number, because the mean of its divisors is an integer number (75814784640).

Almost surely, 2^581720520961 is an apocalyptic number.

It is an amenable number.

581720520961 is a deficient number, since it is larger than the sum of its proper divisors (24797756159).

581720520961 is a wasteful number, since it uses less digits than its factorization.

581720520961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157947623.

The product of its (nonzero) digits is 302400, while the sum is 46.

The spelling of 581720520961 in words is "five hundred eighty-one billion, seven hundred twenty million, five hundred twenty thousand, nine hundred sixty-one".