1916517979 has 2 divisors, whose sum is σ = 1916517980. Its totient is φ = 1916517978.

The previous prime is 1916517937. The next prime is 1916518003. The reversal of 1916517979 is 9797156191.

It is a strong prime.

It is an emirp because it is prime and its reverse (9797156191) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1916517979 - 2⁷ = 1916517851 is a prime.

It is not a weakly prime, because it can be changed into another prime (1916518979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 958258989 + 958258990.

It is an arithmetic number, because the mean of its divisors is an integer number (958258990).

Almost surely, 2^1916517979 is an apocalyptic number.

1916517979 is a deficient number, since it is larger than the sum of its proper divisors (1).

1916517979 is an equidigital number, since it uses as much as digits as its factorization.

1916517979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1071630, while the sum is 55.

The square root of 1916517979 is about 43778.0536227914. The cubic root of 1916517979 is about 1242.1411971050.

The spelling of 1916517979 in words is "one billion, nine hundred sixteen million, five hundred seventeen thousand, nine hundred seventy-nine".