78451 has 4 divisors (see below), whose sum is σ = 82600. Its totient is φ = 74304.

The previous prime is 78439. The next prime is 78467. The reversal of 78451 is 15487.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15487 = 17 ⋅911.

It is a cyclic number.

It is not a de Polignac number, because 78451 - 2¹¹ = 76403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78401) 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, 2046 + ... + 2083.

It is an arithmetic number, because the mean of its divisors is an integer number (20650).

2⁷⁸⁴⁵¹ is an apocalyptic number.

78451 is a deficient number, since it is larger than the sum of its proper divisors (4149).

78451 is a wasteful number, since it uses less digits than its factorization.

78451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4148.

The product of its digits is 1120, while the sum is 25.

The square root of 78451 is about 280.0910566227. The cubic root of 78451 is about 42.8087777146.

It can be divided in two parts, 78 and 451, that added together give a square (529 = 23²).

The spelling of 78451 in words is "seventy-eight thousand, four hundred fifty-one".