20643423043 has 8 divisors (see below), whose sum is σ = 21150249120. Its totient is φ = 20136755520.

The previous prime is 20643423023. The next prime is 20643423067. The reversal of 20643423043 is 34032434602.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20643423043 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20643422996 and 20643423014.

It is not an unprimeable number, because it can be changed into a prime (20643423023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 249513 + ... + 321781.

It is an arithmetic number, because the mean of its divisors is an integer number (2643781140).

Almost surely, 2^20643423043 is an apocalyptic number.

20643423043 is a deficient number, since it is larger than the sum of its proper divisors (506826077).

20643423043 is an equidigital number, since it uses as much as digits as its factorization.

20643423043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79277.

The product of its (nonzero) digits is 41472, while the sum is 31.

Adding to 20643423043 its reverse (34032434602), we get a palindrome (54675857645).

The spelling of 20643423043 in words is "twenty billion, six hundred forty-three million, four hundred twenty-three thousand, forty-three".