421631 has 16 divisors (see below), whose sum is σ = 522240. Its totient is φ = 332640.

The previous prime is 421621. The next prime is 421633. The reversal of 421631 is 136124.

421631 = 50² + 51² + ... + 111².

It is not a de Polignac number, because 421631 - 2¹⁴ = 405247 is a prime.

It is a super-2 number, since 2×421631² = 355545400322, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421633) 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, 6260 + ... + 6326.

It is an arithmetic number, because the mean of its divisors is an integer number (32640).

2⁴²¹⁶³¹ is an apocalyptic number.

421631 is a deficient number, since it is larger than the sum of its proper divisors (100609).

421631 is a wasteful number, since it uses less digits than its factorization.

421631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134.

The product of its digits is 144, while the sum is 17.

The square root of 421631 is about 649.3311943839. The cubic root of 421631 is about 74.9855379522.

Adding to 421631 its reverse (136124), we get a palindrome (557755).

The spelling of 421631 in words is "four hundred twenty-one thousand, six hundred thirty-one".