20606165281 has 8 divisors (see below), whose sum is σ = 22206179240. Its totient is φ = 19008283392.

The previous prime is 20606165243. The next prime is 20606165291. The reversal of 20606165281 is 18256160602.

It can be written as a sum of positive squares in 4 ways, for example, as 423701056 + 20182464225 = 20584^2 + 142065^2 .

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 20606165281 - 2¹⁵ = 20606132513 is a prime.

It is a super-2 number, since 2×20606165281² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20606165281.

It is not an unprimeable number, because it can be changed into a prime (20606165291) 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, 512910 + ... + 551623.

It is an arithmetic number, because the mean of its divisors is an integer number (2775772405).

Almost surely, 2^20606165281 is an apocalyptic number.

It is an amenable number.

20606165281 is a deficient number, since it is larger than the sum of its proper divisors (1600013959).

20606165281 is a wasteful number, since it uses less digits than its factorization.

20606165281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1066035.

The product of its (nonzero) digits is 34560, while the sum is 37.

The spelling of 20606165281 in words is "twenty billion, six hundred six million, one hundred sixty-five thousand, two hundred eighty-one".