421641 has 12 divisors (see below), whose sum is σ = 664560. Its totient is φ = 255480.

The previous prime is 421639. The next prime is 421643. The reversal of 421641 is 146124.

421641 is a `hidden beast` number, since 4 + 21 + 641 = 666.

It is an interprime number because it is at equal distance from previous prime (421639) and next prime (421643).

It is not a de Polignac number, because 421641 - 2¹ = 421639 is a prime.

It is a super-2 number, since 2×421641² = 355562265762, which contains 22 as substring.

421641 is a lucky number.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (421643) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2031 + ... + 2228.

It is an arithmetic number, because the mean of its divisors is an integer number (55380).

2⁴²¹⁶⁴¹ is an apocalyptic number.

It is an amenable number.

421641 is a deficient number, since it is larger than the sum of its proper divisors (242919).

421641 is a wasteful number, since it uses less digits than its factorization.

421641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4276 (or 4273 counting only the distinct ones).

The product of its digits is 192, while the sum is 18.

The square root of 421641 is about 649.3388945689. The cubic root of 421641 is about 74.9861307688.

Adding to 421641 its reverse (146124), we get a palindrome (567765).

The spelling of 421641 in words is "four hundred twenty-one thousand, six hundred forty-one".