1242125123 has 2 divisors, whose sum is σ = 1242125124. Its totient is φ = 1242125122.

The previous prime is 1242125107. The next prime is 1242125141. The reversal of 1242125123 is 3215212421.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1242125123 - 2⁴ = 1242125107 is a prime.

It is not a weakly prime, because it can be changed into another prime (1242125153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621062561 + 621062562.

It is an arithmetic number, because the mean of its divisors is an integer number (621062562).

Almost surely, 2^1242125123 is an apocalyptic number.

1242125123 is a deficient number, since it is larger than the sum of its proper divisors (1).

1242125123 is an equidigital number, since it uses as much as digits as its factorization.

1242125123 is an evil number, because the sum of its binary digits is even.

The product of its digits is 960, while the sum is 23.

The square root of 1242125123 is about 35243.7955248864. The cubic root of 1242125123 is about 1074.9504568478.

Adding to 1242125123 its reverse (3215212421), we get a palindrome (4457337544).

The spelling of 1242125123 in words is "one billion, two hundred forty-two million, one hundred twenty-five thousand, one hundred twenty-three".