20121343243 has 2 divisors, whose sum is σ = 20121343244. Its totient is φ = 20121343242.

The previous prime is 20121343223. The next prime is 20121343343. The reversal of 20121343243 is 34234312102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20121343243 - 2¹³ = 20121335051 is a prime.

It is not a weakly prime, because it can be changed into another prime (20121343223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060671621 + 10060671622.

It is an arithmetic number, because the mean of its divisors is an integer number (10060671622).

Almost surely, 2^20121343243 is an apocalyptic number.

20121343243 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121343243 is an equidigital number, since it uses as much as digits as its factorization.

20121343243 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 20121343243 its reverse (34234312102), we get a palindrome (54355655345).

The spelling of 20121343243 in words is "twenty billion, one hundred twenty-one million, three hundred forty-three thousand, two hundred forty-three".