778404930241391 has 2 divisors, whose sum is σ = 778404930241392. Its totient is φ = 778404930241390.

The previous prime is 778404930241331. The next prime is 778404930241403. The reversal of 778404930241391 is 193142039404877.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-778404930241391 is a prime.

It is a super-2 number, since 2×778404930241391² (a number of 31 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (778404930241331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 389202465120695 + 389202465120696.

It is an arithmetic number, because the mean of its divisors is an integer number (389202465120696).

Almost surely, 2^{778404930241391} is an apocalyptic number.

778404930241391 is a deficient number, since it is larger than the sum of its proper divisors (1).

778404930241391 is an equidigital number, since it uses as much as digits as its factorization.

778404930241391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36578304, while the sum is 62.

The spelling of 778404930241391 in words is "seven hundred seventy-eight trillion, four hundred four billion, nine hundred thirty million, two hundred forty-one thousand, three hundred ninety-one".