17045721021 has 16 divisors (see below), whose sum is σ = 25976365184. Its totient is φ = 9739687104.

The previous prime is 17045721001. The next prime is 17045721071. The reversal of 17045721021 is 12012754071.

It is not a de Polignac number, because 17045721021 - 2¹⁰ = 17045719997 is a prime.

It is a super-2 number, since 2×17045721021² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 17045721021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (17045721001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 403515 + ... + 443751.

It is an arithmetic number, because the mean of its divisors is an integer number (1623522824).

Almost surely, 2^17045721021 is an apocalyptic number.

It is an amenable number.

17045721021 is a deficient number, since it is larger than the sum of its proper divisors (8930644163).

17045721021 is a wasteful number, since it uses less digits than its factorization.

17045721021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60420.

The product of its (nonzero) digits is 3920, while the sum is 30.

The spelling of 17045721021 in words is "seventeen billion, forty-five million, seven hundred twenty-one thousand, twenty-one".