1917879947 has 2 divisors, whose sum is σ = 1917879948. Its totient is φ = 1917879946.

The previous prime is 1917879917. The next prime is 1917880009. The reversal of 1917879947 is 7499787191.

It is an a-pointer prime, because the next prime (1917880009) can be obtained adding 1917879947 to its sum of digits (62).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1917879947 - 2¹⁰ = 1917878923 is a prime.

It is a super-3 number, since 3×1917879947³ (a number of 29 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 1917879947.

It is not a weakly prime, because it can be changed into another prime (1917879917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 958939973 + 958939974.

It is an arithmetic number, because the mean of its divisors is an integer number (958939974).

Almost surely, 2^1917879947 is an apocalyptic number.

1917879947 is a deficient number, since it is larger than the sum of its proper divisors (1).

1917879947 is an equidigital number, since it uses as much as digits as its factorization.

1917879947 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8001504, while the sum is 62.

The square root of 1917879947 is about 43793.6062342438. The cubic root of 1917879947 is about 1242.4353687906.

The spelling of 1917879947 in words is "one billion, nine hundred seventeen million, eight hundred seventy-nine thousand, nine hundred forty-seven".