779949991 has 2 divisors, whose sum is σ = 779949992. Its totient is φ = 779949990.

The previous prime is 779949967. The next prime is 779949997. The reversal of 779949991 is 199949977.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 779949991 - 2⁵ = 779949959 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (779949997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 389974995 + 389974996.

It is an arithmetic number, because the mean of its divisors is an integer number (389974996).

Almost surely, 2^779949991 is an apocalyptic number.

779949991 is a deficient number, since it is larger than the sum of its proper divisors (1).

779949991 is an equidigital number, since it uses as much as digits as its factorization.

779949991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11573604, while the sum is 64.

The square root of 779949991 is about 27927.5847684686. The cubic root of 779949991 is about 920.4967351367.

The spelling of 779949991 in words is "seven hundred seventy-nine million, nine hundred forty-nine thousand, nine hundred ninety-one".