421871 has 4 divisors (see below), whose sum is σ = 423672. Its totient is φ = 420072.

The previous prime is 421847. The next prime is 421891. The reversal of 421871 is 178124.

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 421871 - 2⁶ = 421807 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421801) 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, 485 + ... + 1038.

It is an arithmetic number, because the mean of its divisors is an integer number (105918).

2⁴²¹⁸⁷¹ is an apocalyptic number.

421871 is a deficient number, since it is larger than the sum of its proper divisors (1801).

421871 is a wasteful number, since it uses less digits than its factorization.

421871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1800.

The product of its digits is 448, while the sum is 23.

The square root of 421871 is about 649.5159736296. The cubic root of 421871 is about 74.9997629622. Note that the first 3 decimals are identical.

Adding to 421871 its reverse (178124), we get a palindrome (599995).

The spelling of 421871 in words is "four hundred twenty-one thousand, eight hundred seventy-one".