421000643 has 8 divisors (see below), whose sum is σ = 481743360. Its totient is φ = 360407880.

The previous prime is 421000639. The next prime is 421000649. The reversal of 421000643 is 346000124.

It is a happy number.

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

It is not a de Polignac number, because 421000643 - 2² = 421000639 is a prime.

It is not an unprimeable number, because it can be changed into a prime (421000649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31403 + ... + 42756.

It is an arithmetic number, because the mean of its divisors is an integer number (60217920).

Almost surely, 2^421000643 is an apocalyptic number.

421000643 is a deficient number, since it is larger than the sum of its proper divisors (60742717).

421000643 is an equidigital number, since it uses as much as digits as its factorization.

421000643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74977.

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 421000643 is about 20518.3001976285. The cubic root of 421000643 is about 749.4815041505.

Adding to 421000643 its reverse (346000124), we get a palindrome (767000767).

The spelling of 421000643 in words is "four hundred twenty-one million, six hundred forty-three", and thus it is an aban number.