421646 has 4 divisors (see below), whose sum is σ = 632472. Its totient is φ = 210822.

The previous prime is 421643. The next prime is 421657. The reversal of 421646 is 646124.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421643) 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 as a sum of consecutive naturals, namely, 105410 + ... + 105413.

It is an arithmetic number, because the mean of its divisors is an integer number (158118).

2⁴²¹⁶⁴⁶ is an apocalyptic number.

421646 is a deficient number, since it is larger than the sum of its proper divisors (210826).

421646 is a wasteful number, since it uses less digits than its factorization.

421646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210825.

The product of its digits is 1152, while the sum is 23.

The square root of 421646 is about 649.3427446272. The cubic root of 421646 is about 74.9864271735.

The spelling of 421646 in words is "four hundred twenty-one thousand, six hundred forty-six".