421761 has 4 divisors (see below), whose sum is σ = 562352. Its totient is φ = 281172.

The previous prime is 421741. The next prime is 421783. The reversal of 421761 is 167124.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 421761 - 2⁶ = 421697 is a prime.

It is a super-2 number, since 2×421761² = 355764682242, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (421711) 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, 70291 + ... + 70296.

It is an arithmetic number, because the mean of its divisors is an integer number (140588).

2⁴²¹⁷⁶¹ is an apocalyptic number.

It is an amenable number.

421761 is a deficient number, since it is larger than the sum of its proper divisors (140591).

421761 is a wasteful number, since it uses less digits than its factorization.

421761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140590.

The product of its digits is 336, while the sum is 21.

The square root of 421761 is about 649.4312896681. The cubic root of 421761 is about 74.9932438359.

Adding to 421761 its reverse (167124), we get a palindrome (588885).

It can be divided in two parts, 4217 and 61, that added together give a triangular number (4278 = T₉₂).

The spelling of 421761 in words is "four hundred twenty-one thousand, seven hundred sixty-one".