721641664795 has 8 divisors (see below), whose sum is σ = 866009326896. Its totient is φ = 577287112416.

The previous prime is 721641664729. The next prime is 721641664987. The reversal of 721641664795 is 597466146127.

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 721641664795 - 2¹⁵ = 721641632027 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3155917 + ... + 3376846.

It is an arithmetic number, because the mean of its divisors is an integer number (108251165862).

Almost surely, 2^721641664795 is an apocalyptic number.

721641664795 is a deficient number, since it is larger than the sum of its proper divisors (144367662101).

721641664795 is a wasteful number, since it uses less digits than its factorization.

721641664795 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6554861.

The product of its digits is 15240960, while the sum is 58.

The spelling of 721641664795 in words is "seven hundred twenty-one billion, six hundred forty-one million, six hundred sixty-four thousand, seven hundred ninety-five".