6440779019 has 2 divisors, whose sum is σ = 6440779020. Its totient is φ = 6440779018.

The previous prime is 6440778947. The next prime is 6440779021. The reversal of 6440779019 is 9109770446.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6440779019 - 2²⁰ = 6439730443 is a prime.

It is a super-2 number, since 2×6440779019² = 82967268743181204722, which contains 22 as substring.

Together with 6440779021, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (6440779039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3220389509 + 3220389510.

It is an arithmetic number, because the mean of its divisors is an integer number (3220389510).

Almost surely, 2^6440779019 is an apocalyptic number.

6440779019 is a deficient number, since it is larger than the sum of its proper divisors (1).

6440779019 is an equidigital number, since it uses as much as digits as its factorization.

6440779019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 381024, while the sum is 47.

The square root of 6440779019 is about 80254.4641686679. The cubic root of 6440779019 is about 1860.5705093682.

The spelling of 6440779019 in words is "six billion, four hundred forty million, seven hundred seventy-nine thousand, nineteen".