21423100043 has 2 divisors, whose sum is σ = 21423100044. Its totient is φ = 21423100042.

The previous prime is 21423100019. The next prime is 21423100073. The reversal of 21423100043 is 34000132412.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21423100043 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21423099988 and 21423100024.

It is not a weakly prime, because it can be changed into another prime (21423100003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10711550021 + 10711550022.

It is an arithmetic number, because the mean of its divisors is an integer number (10711550022).

Almost surely, 2^21423100043 is an apocalyptic number.

21423100043 is a deficient number, since it is larger than the sum of its proper divisors (1).

21423100043 is an equidigital number, since it uses as much as digits as its factorization.

21423100043 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21423100043 its reverse (34000132412), we get a palindrome (55423232455).

The spelling of 21423100043 in words is "twenty-one billion, four hundred twenty-three million, one hundred thousand, forty-three".