778343868343877 has 4 divisors (see below), whose sum is σ = 849102401829696. Its totient is φ = 707585334858060.

The previous prime is 778343868343837. The next prime is 778343868343891.

It is a happy number.

778343868343877 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-778343868343877 is a prime.

It is a super-2 number, since 2×778343868343877² (a number of 31 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (778343868343837) 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, 35379266742893 + ... + 35379266742914.

It is an arithmetic number, because the mean of its divisors is an integer number (212275600457424).

Almost surely, 2^{778343868343877} is an apocalyptic number.

It is an amenable number.

778343868343877 is a deficient number, since it is larger than the sum of its proper divisors (70758533485819).

778343868343877 is a wasteful number, since it uses less digits than its factorization.

778343868343877 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70758533485818.

The product of its digits is 76473040896, while the sum is 86.

The spelling of 778343868343877 in words is "seven hundred seventy-eight trillion, three hundred forty-three billion, eight hundred sixty-eight million, three hundred forty-three thousand, eight hundred seventy-seven".