20323632055561 has 4 divisors (see below), whose sum is σ = 20872919408452. Its totient is φ = 19774344702672.

The previous prime is 20323632055553. The next prime is 20323632055583. The reversal of 20323632055561 is 16555023632302.

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 18706490010000 + 1617142045561 = 4325100^2 + 1271669^2 .

It is a cyclic number.

It is not a de Polignac number, because 20323632055561 - 2³ = 20323632055553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20323632055511) 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, 274643676390 + ... + 274643676463.

It is an arithmetic number, because the mean of its divisors is an integer number (5218229852113).

Almost surely, 2^{20323632055561} is an apocalyptic number.

It is an amenable number.

20323632055561 is a deficient number, since it is larger than the sum of its proper divisors (549287352891).

20323632055561 is an equidigital number, since it uses as much as digits as its factorization.

20323632055561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 549287352890.

The product of its (nonzero) digits is 972000, while the sum is 43.

Adding to 20323632055561 its reverse (16555023632302), we get a palindrome (36878655687863).

The spelling of 20323632055561 in words is "twenty trillion, three hundred twenty-three billion, six hundred thirty-two million, fifty-five thousand, five hundred sixty-one".