78257521216385 has 8 divisors (see below), whose sum is σ = 107324600525376. Its totient is φ = 53662300262640.

The previous prime is 78257521216361. The next prime is 78257521216403. The reversal of 78257521216385 is 58361212575287.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 78257521216385 - 2³⁰ = 78256447474561 is a prime.

It is a super-2 number, since 2×78257521216385² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1117964588771 + ... + 1117964588840.

It is an arithmetic number, because the mean of its divisors is an integer number (13415575065672).

Almost surely, 2^{78257521216385} is an apocalyptic number.

It is an amenable number.

78257521216385 is a deficient number, since it is larger than the sum of its proper divisors (29067079308991).

78257521216385 is a wasteful number, since it uses less digits than its factorization.

78257521216385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2235929177623.

The product of its digits is 56448000, while the sum is 62.

The spelling of 78257521216385 in words is "seventy-eight trillion, two hundred fifty-seven billion, five hundred twenty-one million, two hundred sixteen thousand, three hundred eighty-five".