1242511279 has 4 divisors (see below), whose sum is σ = 1282592320. Its totient is φ = 1202430240.

The previous prime is 1242511211. The next prime is 1242511297. The reversal of 1242511279 is 9721152421.

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 1242511279 - 2⁹ = 1242510767 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1242511579) 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, 20040474 + ... + 20040535.

It is an arithmetic number, because the mean of its divisors is an integer number (320648080).

Almost surely, 2^1242511279 is an apocalyptic number.

1242511279 is a deficient number, since it is larger than the sum of its proper divisors (40081041).

1242511279 is an equidigital number, since it uses as much as digits as its factorization.

1242511279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40081040.

The product of its digits is 10080, while the sum is 34.

The square root of 1242511279 is about 35249.2734535054. The cubic root of 1242511279 is about 1075.0618400337.

The spelling of 1242511279 in words is "one billion, two hundred forty-two million, five hundred eleven thousand, two hundred seventy-nine".