20420340433243 has 4 divisors (see below), whose sum is σ = 20421106960408. Its totient is φ = 20419573906080.

The previous prime is 20420340433169. The next prime is 20420340433271. The reversal of 20420340433243 is 34233404302402.

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-20420340433243 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20420340433199 and 20420340433208.

It is not an unprimeable number, because it can be changed into a prime (20420340439243) 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, 383223621 + ... + 383276902.

It is an arithmetic number, because the mean of its divisors is an integer number (5105276740102).

Almost surely, 2^{20420340433243} is an apocalyptic number.

20420340433243 is a deficient number, since it is larger than the sum of its proper divisors (766527165).

20420340433243 is an equidigital number, since it uses as much as digits as its factorization.

20420340433243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 766527164.

The product of its (nonzero) digits is 165888, while the sum is 34.

Adding to 20420340433243 its reverse (34233404302402), we get a palindrome (54653744735645).

The spelling of 20420340433243 in words is "twenty trillion, four hundred twenty billion, three hundred forty million, four hundred thirty-three thousand, two hundred forty-three".