779999999999999 has 4 divisors (see below), whose sum is σ = 782508038585520. Its totient is φ = 777491961414480.

The previous prime is 779999999999951. The next prime is 780000000000007. The reversal of 779999999999999 is 999999999999977.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 779999999999999 - 2¹² = 779999999995903 is a prime.

It is a super-9 number, since 9×779999999999999⁹ (a number of 135 digits) contains 999999999 as substring.

It is a Duffinian number.

779999999999999 is a modest number, since divided by 99999999 gives 7799999 as remainder.

It is a plaindrome in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (779999999969999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1254019292294 + ... + 1254019292915.

It is an arithmetic number, because the mean of its divisors is an integer number (195627009646380).

Almost surely, 2^{779999999999999} is an apocalyptic number.

779999999999999 is a deficient number, since it is larger than the sum of its proper divisors (2508038585521).

779999999999999 is a wasteful number, since it uses less digits than its factorization.

779999999999999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2508038585520.

The product of its digits is 124551425588121, while the sum is 131.

The spelling of 779999999999999 in words is "seven hundred seventy-nine trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-nine".