420491 has 4 divisors (see below), whose sum is σ = 421800. Its totient is φ = 419184.

The previous prime is 420481. The next prime is 420499. The reversal of 420491 is 194024.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 420491 - 2¹⁰ = 419467 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (420499) 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, 200 + ... + 938.

It is an arithmetic number, because the mean of its divisors is an integer number (105450).

2⁴²⁰⁴⁹¹ is an apocalyptic number.

420491 is a deficient number, since it is larger than the sum of its proper divisors (1309).

420491 is an equidigital number, since it uses as much as digits as its factorization.

420491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1308.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 420491 is about 648.4527739165. The cubic root of 420491 is about 74.9178953356.

The spelling of 420491 in words is "four hundred twenty thousand, four hundred ninety-one".