1243123423 has 2 divisors, whose sum is σ = 1243123424. Its totient is φ = 1243123422.

The previous prime is 1243123417. The next prime is 1243123457. The reversal of 1243123423 is 3243213421.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1243123423 - 2¹³ = 1243115231 is a prime.

It is a super-2 number, since 2×1243123423² = 3090711689622473858, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1243123493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621561711 + 621561712.

It is an arithmetic number, because the mean of its divisors is an integer number (621561712).

Almost surely, 2^1243123423 is an apocalyptic number.

1243123423 is a deficient number, since it is larger than the sum of its proper divisors (1).

1243123423 is an equidigital number, since it uses as much as digits as its factorization.

1243123423 is an evil number, because the sum of its binary digits is even.

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

The square root of 1243123423 is about 35257.9554568894. The cubic root of 1243123423 is about 1075.2383601244.

Adding to 1243123423 its reverse (3243213421), we get a palindrome (4486336844).

The spelling of 1243123423 in words is "one billion, two hundred forty-three million, one hundred twenty-three thousand, four hundred twenty-three".