20363431031561 has 16 divisors (see below), whose sum is σ = 20932119740160. Its totient is φ = 19795713275520.

The previous prime is 20363431031549. The next prime is 20363431031651. The reversal of 20363431031561 is 16513013436302.

It is a cyclic number.

It is not a de Polignac number, because 20363431031561 - 2³⁰ = 20362357289737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20363431031161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 242984576 + ... + 243068366.

It is an arithmetic number, because the mean of its divisors is an integer number (1308257483760).

Almost surely, 2^{20363431031561} is an apocalyptic number.

It is an amenable number.

20363431031561 is a deficient number, since it is larger than the sum of its proper divisors (568688708599).

20363431031561 is a wasteful number, since it uses less digits than its factorization.

20363431031561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89504.

The product of its (nonzero) digits is 116640, while the sum is 38.

Adding to 20363431031561 its reverse (16513013436302), we get a palindrome (36876444467863).

The spelling of 20363431031561 in words is "twenty trillion, three hundred sixty-three billion, four hundred thirty-one million, thirty-one thousand, five hundred sixty-one".