781216019 has 2 divisors, whose sum is σ = 781216020. Its totient is φ = 781216018.

The previous prime is 781215961. The next prime is 781216031. The reversal of 781216019 is 910612187.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 781216019 - 2¹⁶ = 781150483 is a prime.

It is a super-2 number, since 2×781216019² = 1220596936684416722, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 781216019.

It is not a weakly prime, because it can be changed into another prime (781216519) 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, 390608009 + 390608010.

It is an arithmetic number, because the mean of its divisors is an integer number (390608010).

Almost surely, 2^781216019 is an apocalyptic number.

781216019 is a deficient number, since it is larger than the sum of its proper divisors (1).

781216019 is an equidigital number, since it uses as much as digits as its factorization.

781216019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6048, while the sum is 35.

The square root of 781216019 is about 27950.2418415297. The cubic root of 781216019 is about 920.9945211786.

The spelling of 781216019 in words is "seven hundred eighty-one million, two hundred sixteen thousand, nineteen".