20005331244251 has 4 divisors (see below), whose sum is σ = 20546015872512. Its totient is φ = 19464646615992.

The previous prime is 20005331244211. The next prime is 20005331244257. The reversal of 20005331244251 is 15244213350002.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20005331244251 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20005331244257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 270342314075 + ... + 270342314148.

It is an arithmetic number, because the mean of its divisors is an integer number (5136503968128).

Almost surely, 2^{20005331244251} is an apocalyptic number.

20005331244251 is a deficient number, since it is larger than the sum of its proper divisors (540684628261).

20005331244251 is an equidigital number, since it uses as much as digits as its factorization.

20005331244251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 540684628260.

The product of its (nonzero) digits is 28800, while the sum is 32.

Adding to 20005331244251 its reverse (15244213350002), we get a palindrome (35249544594253).

The spelling of 20005331244251 in words is "twenty trillion, five billion, three hundred thirty-one million, two hundred forty-four thousand, two hundred fifty-one".