1242779779 has 8 divisors (see below), whose sum is σ = 1264361040. Its totient is φ = 1221237600.

The previous prime is 1242779773. The next prime is 1242779789. The reversal of 1242779779 is 9779772421.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1242779779 - 2⁷ = 1242779651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1242779773) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58464 + ... + 76834.

It is an arithmetic number, because the mean of its divisors is an integer number (158045130).

Almost surely, 2^1242779779 is an apocalyptic number.

1242779779 is a deficient number, since it is larger than the sum of its proper divisors (21581261).

1242779779 is a wasteful number, since it uses less digits than its factorization.

1242779779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19541.

The product of its digits is 3111696, while the sum is 55.

The square root of 1242779779 is about 35253.0818369118. The cubic root of 1242779779 is about 1075.1392728155.

The spelling of 1242779779 in words is "one billion, two hundred forty-two million, seven hundred seventy-nine thousand, seven hundred seventy-nine".