478991 has 2 divisors, whose sum is σ = 478992. Its totient is φ = 478990.

The previous prime is 478967. The next prime is 478999. The reversal of 478991 is 199874.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 478991 - 2⁶ = 478927 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (478999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 239495 + 239496.

It is an arithmetic number, because the mean of its divisors is an integer number (239496).

2⁴⁷⁸⁹⁹¹ is an apocalyptic number.

478991 is a deficient number, since it is larger than the sum of its proper divisors (1).

478991 is an equidigital number, since it uses as much as digits as its factorization.

478991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 38.

The square root of 478991 is about 692.0917569224. The cubic root of 478991 is about 78.2424518164.

The spelling of 478991 in words is "four hundred seventy-eight thousand, nine hundred ninety-one".