78839851 has 4 divisors (see below), whose sum is σ = 81383104. Its totient is φ = 76296600.

The previous prime is 78839807. The next prime is 78839857. The reversal of 78839851 is 15893887.

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 78839851 - 2⁷ = 78839723 is a prime.

It is a super-3 number, since 3×78839851³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78839795 and 78839804.

It is not an unprimeable number, because it can be changed into a prime (78839857) 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, 1271580 + ... + 1271641.

It is an arithmetic number, because the mean of its divisors is an integer number (20345776).

Almost surely, 2^78839851 is an apocalyptic number.

78839851 is a deficient number, since it is larger than the sum of its proper divisors (2543253).

78839851 is a wasteful number, since it uses less digits than its factorization.

78839851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2543252.

The product of its digits is 483840, while the sum is 49.

The square root of 78839851 is about 8879.1807617595. The cubic root of 78839851 is about 428.7938998022.

The spelling of 78839851 in words is "seventy-eight million, eight hundred thirty-nine thousand, eight hundred fifty-one".