1243223123 has 4 divisors (see below), whose sum is σ = 1261778760. Its totient is φ = 1224667488.

The previous prime is 1243223119. The next prime is 1243223131. The reversal of 1243223123 is 3213223421.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1243223123 - 2² = 1243223119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1243220123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9277718 + ... + 9277851.

It is an arithmetic number, because the mean of its divisors is an integer number (315444690).

Almost surely, 2^1243223123 is an apocalyptic number.

1243223123 is a deficient number, since it is larger than the sum of its proper divisors (18555637).

1243223123 is an equidigital number, since it uses as much as digits as its factorization.

1243223123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18555636.

The product of its digits is 1728, while the sum is 23.

The square root of 1243223123 is about 35259.3692938487. The cubic root of 1243223123 is about 1075.2671044944.

Adding to 1243223123 its reverse (3213223421), we get a palindrome (4456446544).

The spelling of 1243223123 in words is "one billion, two hundred forty-three million, two hundred twenty-three thousand, one hundred twenty-three".