421887 has 4 divisors (see below), whose sum is σ = 562520. Its totient is φ = 281256.

The previous prime is 421847. The next prime is 421891. The reversal of 421887 is 788124.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 421887 - 2¹⁶ = 356351 is a prime.

It is a super-3 number, since 3×421887³ = 225273281064333309, which contains 333 as substring.

It is a D-number.

It is a Duffinian number.

It is a plaindrome in base 8 and base 16.

It is a zygodrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421807) 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, 70312 + ... + 70317.

It is an arithmetic number, because the mean of its divisors is an integer number (140630).

2⁴²¹⁸⁸⁷ is an apocalyptic number.

421887 is a deficient number, since it is larger than the sum of its proper divisors (140633).

421887 is a wasteful number, since it uses less digits than its factorization.

421887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140632.

The product of its digits is 3584, while the sum is 30.

The square root of 421887 is about 649.5282903769. The cubic root of 421887 is about 75.0007111044. Note that the first 3 decimals are identical.

It can be divided in two parts, 42188 and 7, that added together give a triangular number (42195 = T₂₉₀).

The spelling of 421887 in words is "four hundred twenty-one thousand, eight hundred eighty-seven".