20013322561 has 8 divisors (see below), whose sum is σ = 20269122440. Its totient is φ = 19758532608.

The previous prime is 20013322541. The next prime is 20013322597. The reversal of 20013322561 is 16522331002.

It can be written as a sum of positive squares in 4 ways, for example, as 6237840400 + 13775482161 = 78980^2 + 117369^2 .

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 20013322561 - 2⁵ = 20013322529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20013322541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 212556 + ... + 291901.

It is an arithmetic number, because the mean of its divisors is an integer number (2533640305).

Almost surely, 2^20013322561 is an apocalyptic number.

It is an amenable number.

20013322561 is a deficient number, since it is larger than the sum of its proper divisors (255799879).

20013322561 is an equidigital number, since it uses as much as digits as its factorization.

20013322561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 504963.

The product of its (nonzero) digits is 2160, while the sum is 25.

Adding to 20013322561 its reverse (16522331002), we get a palindrome (36535653563).

The spelling of 20013322561 in words is "twenty billion, thirteen million, three hundred twenty-two thousand, five hundred sixty-one".