78851 has 4 divisors (see below), whose sum is σ = 81600. Its totient is φ = 76104.

The previous prime is 78839. The next prime is 78853. The reversal of 78851 is 15887.

It is a happy number.

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 78851 - 2⁶ = 78787 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 2719 = 78851 / (7 + 8 + 8 + 5 + 1).

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78853) 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, 1331 + ... + 1388.

It is an arithmetic number, because the mean of its divisors is an integer number (20400).

2⁷⁸⁸⁵¹ is an apocalyptic number.

78851 is a deficient number, since it is larger than the sum of its proper divisors (2749).

78851 is a wasteful number, since it uses less digits than its factorization.

78851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2748.

The product of its digits is 2240, while the sum is 29.

The square root of 78851 is about 280.8042022478. The cubic root of 78851 is about 42.8814111230.

It can be divided in two parts, 78 and 851, that added together give a palindrome (929).

The spelling of 78851 in words is "seventy-eight thousand, eight hundred fifty-one".