420891 has 4 divisors (see below), whose sum is σ = 561192. Its totient is φ = 280592.

The previous prime is 420859. The next prime is 420899. The reversal of 420891 is 198024.

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 420891 - 2⁵ = 420859 is a prime.

It is a D-number.

420891 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (420899) 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, 70146 + ... + 70151.

It is an arithmetic number, because the mean of its divisors is an integer number (140298).

2⁴²⁰⁸⁹¹ is an apocalyptic number.

420891 is a deficient number, since it is larger than the sum of its proper divisors (140301).

420891 is a wasteful number, since it uses less digits than its factorization.

420891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140300.

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 420891 is about 648.7611270722. The cubic root of 420891 is about 74.9416434942.

The spelling of 420891 in words is "four hundred twenty thousand, eight hundred ninety-one".