20166220265 has 4 divisors (see below), whose sum is σ = 24199464324. Its totient is φ = 16132976208.

The previous prime is 20166220259. The next prime is 20166220313. The reversal of 20166220265 is 56202266102.

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 10243868944 + 9922351321 = 101212^2 + 99611^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20166220265 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 2016622022 + ... + 2016622031.

It is an arithmetic number, because the mean of its divisors is an integer number (6049866081).

Almost surely, 2^20166220265 is an apocalyptic number.

It is an amenable number.

20166220265 is a deficient number, since it is larger than the sum of its proper divisors (4033244059).

20166220265 is an equidigital number, since it uses as much as digits as its factorization.

20166220265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4033244058.

The product of its (nonzero) digits is 17280, while the sum is 32.

Adding to 20166220265 its reverse (56202266102), we get a palindrome (76368486367).

The spelling of 20166220265 in words is "twenty billion, one hundred sixty-six million, two hundred twenty thousand, two hundred sixty-five".