421689 has 16 divisors (see below), whose sum is σ = 601920. Its totient is φ = 262080.

The previous prime is 421661. The next prime is 421691. The reversal of 421689 is 986124.

It is not a de Polignac number, because 421689 - 2⁵ = 421657 is a prime.

It is a super-2 number, since 2×421689² = 355643225442, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (421609) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3154 + ... + 3284.

It is an arithmetic number, because the mean of its divisors is an integer number (37620).

2⁴²¹⁶⁸⁹ is an apocalyptic number.

It is an amenable number.

421689 is a deficient number, since it is larger than the sum of its proper divisors (180231).

421689 is a wasteful number, since it uses less digits than its factorization.

421689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200.

The product of its digits is 3456, while the sum is 30.

The square root of 421689 is about 649.3758541862. The cubic root of 421689 is about 74.9889761575.

The spelling of 421689 in words is "four hundred twenty-one thousand, six hundred eighty-nine".