778999999999 has 4 divisors (see below), whose sum is σ = 838923076936. Its totient is φ = 719076923064.

The previous prime is 778999999993. The next prime is 779000000003. The reversal of 778999999999 is 999999999877.

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 778999999999 - 2⁷ = 778999999871 is a prime.

It is a Duffinian number.

778999999999 is a modest number, since divided by 999999 gives 778999 as remainder.

It is a plaindrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 778999999898 and 778999999907.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (778999999993) 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, 29961538449 + ... + 29961538474.

It is an arithmetic number, because the mean of its divisors is an integer number (209730769234).

Almost surely, 2^778999999999 is an apocalyptic number.

778999999999 is a deficient number, since it is larger than the sum of its proper divisors (59923076937).

778999999999 is a wasteful number, since it uses less digits than its factorization.

778999999999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59923076936.

The product of its digits is 151868831688, while the sum is 103.

The spelling of 778999999999 in words is "seven hundred seventy-eight billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-nine".