20275481665 has 4 divisors (see below), whose sum is σ = 24330578004. Its totient is φ = 16220385328.

The previous prime is 20275481651. The next prime is 20275481713. The reversal of 20275481665 is 56618457202.

It is a Cunningham number, because it is equal to 142392²+1.

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 7299310096 + 12976171569 = 85436^2 + 113913^2 .

It is a cyclic number.

It is not a de Polignac number, because 20275481665 - 2⁷ = 20275481537 is a prime.

It is a super-2 number, since 2×20275481665² (a number of 21 digits) contains 22 as substring.

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, 2027548162 + ... + 2027548171.

It is an arithmetic number, because the mean of its divisors is an integer number (6082644501).

Almost surely, 2^20275481665 is an apocalyptic number.

It is an amenable number.

20275481665 is a deficient number, since it is larger than the sum of its proper divisors (4055096339).

20275481665 is an equidigital number, since it uses as much as digits as its factorization.

20275481665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4055096338.

The product of its (nonzero) digits is 806400, while the sum is 46.

The spelling of 20275481665 in words is "twenty billion, two hundred seventy-five million, four hundred eighty-one thousand, six hundred sixty-five".