20927219564161 has 4 divisors (see below), whose sum is σ = 20936641997524. Its totient is φ = 20917797130800.

The previous prime is 20927219564123. The next prime is 20927219564171. The reversal of 20927219564161 is 16146591272902.

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 7185696778225 + 13741522785936 = 2680615^2 + 3706956^2 .

It is a cyclic number.

It is not a de Polignac number, because 20927219564161 - 2³⁵ = 20892859825793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20927219564171) 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, 4711213350 + ... + 4711217791.

It is an arithmetic number, because the mean of its divisors is an integer number (5234160499381).

Almost surely, 2^{20927219564161} is an apocalyptic number.

It is an amenable number.

20927219564161 is a deficient number, since it is larger than the sum of its proper divisors (9422433363).

20927219564161 is an equidigital number, since it uses as much as digits as its factorization.

20927219564161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9422433362.

The product of its (nonzero) digits is 3265920, while the sum is 55.

The spelling of 20927219564161 in words is "twenty trillion, nine hundred twenty-seven billion, two hundred nineteen million, five hundred sixty-four thousand, one hundred sixty-one".