78857417389 has 4 divisors (see below), whose sum is σ = 78865960060. Its totient is φ = 78848874720.

The previous prime is 78857417341. The next prime is 78857417399. The reversal of 78857417389 is 98371475887.

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

It can be written as a sum of positive squares in 2 ways, for example, as 59794920900 + 19062496489 = 244530^2 + 138067^2 .

It is a cyclic number.

It is not a de Polignac number, because 78857417389 - 2²³ = 78849028781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78857417329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4257474 + ... + 4275955.

It is an arithmetic number, because the mean of its divisors is an integer number (19716490015).

Almost surely, 2^78857417389 is an apocalyptic number.

It is an amenable number.

78857417389 is a deficient number, since it is larger than the sum of its proper divisors (8542671).

78857417389 is an equidigital number, since it uses as much as digits as its factorization.

78857417389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8542670.

The product of its digits is 94832640, while the sum is 67.

The spelling of 78857417389 in words is "seventy-eight billion, eight hundred fifty-seven million, four hundred seventeen thousand, three hundred eighty-nine".