641722321 has 8 divisors (see below), whose sum is σ = 675734400. Its totient is φ = 607734000.

The previous prime is 641722267. The next prime is 641722327. The reversal of 641722321 is 123227146.

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

It is not a de Polignac number, because 641722321 - 2¹¹ = 641720273 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 641722321.

It is not an unprimeable number, because it can be changed into a prime (641722327) 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, 86715 + ... + 93823.

It is an arithmetic number, because the mean of its divisors is an integer number (84466800).

Almost surely, 2^641722321 is an apocalyptic number.

It is an amenable number.

641722321 is a deficient number, since it is larger than the sum of its proper divisors (34012079).

641722321 is a wasteful number, since it uses less digits than its factorization.

641722321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11879.

The product of its digits is 4032, while the sum is 28.

The square root of 641722321 is about 25332.2387680205. The cubic root of 641722321 is about 862.5462311143.

Adding to 641722321 its reverse (123227146), we get a palindrome (764949467).

The spelling of 641722321 in words is "six hundred forty-one million, seven hundred twenty-two thousand, three hundred twenty-one".