478921 has 4 divisors (see below), whose sum is σ = 490644. Its totient is φ = 467200.

The previous prime is 478913. The next prime is 478927. The reversal of 478921 is 129874.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 129874 = 2 ⋅64937.

It can be written as a sum of positive squares in 2 ways, for example, as 112896 + 366025 = 336^2 + 605^2 .

It is a cyclic number.

It is not a de Polignac number, because 478921 - 2³ = 478913 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (478927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5800 + ... + 5881.

It is an arithmetic number, because the mean of its divisors is an integer number (122661).

2⁴⁷⁸⁹²¹ is an apocalyptic number.

478921 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

It is an amenable number.

478921 is a deficient number, since it is larger than the sum of its proper divisors (11723).

478921 is a wasteful number, since it uses less digits than its factorization.

478921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11722.

The product of its digits is 4032, while the sum is 31.

The square root of 478921 is about 692.0411837456. The cubic root of 478921 is about 78.2386401662.

The spelling of 478921 in words is "four hundred seventy-eight thousand, nine hundred twenty-one".