1917243139 has 6 divisors (see below), whose sum is σ = 2230262484. Its totient is φ = 1643351220.

The previous prime is 1917243109. The next prime is 1917243149. The reversal of 1917243139 is 9313427191.

It is not a de Polignac number, because 1917243139 - 2⁷ = 1917243011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1917243109) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 19563657 + ... + 19563754.

It is an arithmetic number, because the mean of its divisors is an integer number (371710414).

Almost surely, 2^1917243139 is an apocalyptic number.

1917243139 is a deficient number, since it is larger than the sum of its proper divisors (313019345).

1917243139 is an equidigital number, since it uses as much as digits as its factorization.

1917243139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39127425 (or 39127418 counting only the distinct ones).

The product of its digits is 40824, while the sum is 40.

The square root of 1917243139 is about 43786.3350715723. The cubic root of 1917243139 is about 1242.2978418704.

The spelling of 1917243139 in words is "one billion, nine hundred seventeen million, two hundred forty-three thousand, one hundred thirty-nine".