20445025520065 has 4 divisors (see below), whose sum is σ = 24534030624084. Its totient is φ = 16356020416048.

The previous prime is 20445025520033. The next prime is 20445025520069. The reversal of 20445025520065 is 56002552054402.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4415507918721 + 16029517601344 = 2101311^2 + 4003688^2 .

It is a cyclic number.

It is not a de Polignac number, because 20445025520065 - 2⁵ = 20445025520033 is a prime.

It is a super-2 number, since 2×20445025520065² (a number of 27 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (40) 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 (20445025520069) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2044502552002 + ... + 2044502552011.

It is an arithmetic number, because the mean of its divisors is an integer number (6133507656021).

Almost surely, 2^{20445025520065} is an apocalyptic number.

It is an amenable number.

20445025520065 is a deficient number, since it is larger than the sum of its proper divisors (4089005104019).

20445025520065 is an equidigital number, since it uses as much as digits as its factorization.

20445025520065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4089005104018.

The product of its (nonzero) digits is 480000, while the sum is 40.

Adding to 20445025520065 its reverse (56002552054402), we get a palindrome (76447577574467).

The spelling of 20445025520065 in words is "twenty trillion, four hundred forty-five billion, twenty-five million, five hundred twenty thousand, sixty-five".