1720563657051 has 16 divisors (see below), whose sum is σ = 2331921302048. Its totient is φ = 1128127910400.

The previous prime is 1720563657023. The next prime is 1720563657067. The reversal of 1720563657051 is 1507563650271.

It is not a de Polignac number, because 1720563657051 - 2¹⁰ = 1720563656027 is a prime.

It is a super-2 number, since 2×1720563657051² (a number of 25 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1720563657851) 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, 1433265 + ... + 2344221.

It is an arithmetic number, because the mean of its divisors is an integer number (145745081378).

Almost surely, 2^{1720563657051} is an apocalyptic number.

1720563657051 is a deficient number, since it is larger than the sum of its proper divisors (611357644997).

1720563657051 is a wasteful number, since it uses less digits than its factorization.

1720563657051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 921342.

The product of its (nonzero) digits is 1323000, while the sum is 48.

The spelling of 1720563657051 in words is "one trillion, seven hundred twenty billion, five hundred sixty-three million, six hundred fifty-seven thousand, fifty-one".