421729 has 8 divisors (see below), whose sum is σ = 525888. Its totient is φ = 328560.

The previous prime is 421727. The next prime is 421739. The reversal of 421729 is 927124.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 421729 - 2¹ = 421727 is a prime.

It is not an unprimeable number, because it can be changed into a prime (421727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2662 + ... + 2815.

It is an arithmetic number, because the mean of its divisors is an integer number (65736).

2⁴²¹⁷²⁹ is an apocalyptic number.

It is an amenable number.

421729 is a deficient number, since it is larger than the sum of its proper divisors (104159).

421729 is a wasteful number, since it uses less digits than its factorization.

421729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5495.

The product of its digits is 1008, while the sum is 25.

The square root of 421729 is about 649.4066522604. The cubic root of 421729 is about 74.9913471499.

It can be divided in two parts, 42 and 1729, that added together give a palindrome (1771).

The spelling of 421729 in words is "four hundred twenty-one thousand, seven hundred twenty-nine".