778135216375 has 24 divisors (see below), whose sum is σ = 1059440262192. Its totient is φ = 565892732000.

The previous prime is 778135216361. The next prime is 778135216399. The reversal of 778135216375 is 573612531877.

It is not a de Polignac number, because 778135216375 - 2⁵ = 778135216343 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (55).

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 32697981 + ... + 32721769.

It is an arithmetic number, because the mean of its divisors is an integer number (44143344258).

Almost surely, 2^778135216375 is an apocalyptic number.

778135216375 is a deficient number, since it is larger than the sum of its proper divisors (281305045817).

778135216375 is an frugal number, since it uses more digits than its factorization.

778135216375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47604 (or 23805 counting only the distinct ones).

The product of its digits is 7408800, while the sum is 55.

Multiplying 778135216375 by its sum of digits (55), we get a square (42797436900625 = 6541975²).

778135216375 divided by its sum of digits (55) gives a square (14147913025 = 118945²).

The spelling of 778135216375 in words is "seven hundred seventy-eight billion, one hundred thirty-five million, two hundred sixteen thousand, three hundred seventy-five".