1278242473 has 4 divisors (see below), whose sum is σ = 1279102420. Its totient is φ = 1277382528.

The previous prime is 1278242443. The next prime is 1278242491. The reversal of 1278242473 is 3742428721.

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

It can be written as a sum of positive squares in 2 ways, for example, as 645820569 + 632421904 = 25413^2 + 25148^2 .

It is a cyclic number.

It is not a de Polignac number, because 1278242473 - 2²⁵ = 1244688041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1278242443) 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, 427740 + ... + 430717.

It is an arithmetic number, because the mean of its divisors is an integer number (319775605).

Almost surely, 2^1278242473 is an apocalyptic number.

It is an amenable number.

1278242473 is a deficient number, since it is larger than the sum of its proper divisors (859947).

1278242473 is an equidigital number, since it uses as much as digits as its factorization.

1278242473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 859946.

The product of its digits is 150528, while the sum is 40.

The square root of 1278242473 is about 35752.5170162885. The cubic root of 1278242473 is about 1085.2698750339.

It can be divided in two parts, 12782 and 42473, that added together give a palindrome (55255).

The spelling of 1278242473 in words is "one billion, two hundred seventy-eight million, two hundred forty-two thousand, four hundred seventy-three".