20434220243 has 4 divisors (see below), whose sum is σ = 20434590240. Its totient is φ = 20433850248.

The previous prime is 20434220239. The next prime is 20434220311. The reversal of 20434220243 is 34202243402.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34202243402 = 2 ⋅17101121701.

It is a cyclic number.

It is not a de Polignac number, because 20434220243 - 2² = 20434220239 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20434220203) 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 3 ways as a sum of consecutive naturals, for example, 83648 + ... + 218781.

It is an arithmetic number, because the mean of its divisors is an integer number (5108647560).

Almost surely, 2^20434220243 is an apocalyptic number.

20434220243 is a deficient number, since it is larger than the sum of its proper divisors (369997).

20434220243 is an equidigital number, since it uses as much as digits as its factorization.

20434220243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 369996.

The product of its (nonzero) digits is 9216, while the sum is 26.

Adding to 20434220243 its reverse (34202243402), we get a palindrome (54636463645).

The spelling of 20434220243 in words is "twenty billion, four hundred thirty-four million, two hundred twenty thousand, two hundred forty-three".