78857739739 has 4 divisors (see below), whose sum is σ = 78882880824. Its totient is φ = 78832598656.

The previous prime is 78857739721. The next prime is 78857739743. The reversal of 78857739739 is 93793775887.

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 78857739739 - 2¹¹ = 78857737691 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78857739769) 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, 12565837 + ... + 12572110.

It is an arithmetic number, because the mean of its divisors is an integer number (19720720206).

Almost surely, 2^78857739739 is an apocalyptic number.

78857739739 is a deficient number, since it is larger than the sum of its proper divisors (25141085).

78857739739 is a wasteful number, since it uses less digits than its factorization.

78857739739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25141084.

The product of its digits is 560105280, while the sum is 73.

The spelling of 78857739739 in words is "seventy-eight billion, eight hundred fifty-seven million, seven hundred thirty-nine thousand, seven hundred thirty-nine".