406643 has 4 divisors (see below), whose sum is σ = 409488.
Its totient is φ = 403800.
The previous prime is 406633. The next prime is 406649. The reversal of 406643 is 346604.
It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is not a de Polignac number, because 406643 - 26 = 406579 is a prime.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (406649) 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, 1196 + ... + 1497.
It is an arithmetic number, because the mean of its divisors is an integer number (102372).
2406643 is an apocalyptic number.
406643 is a deficient number, since it is larger than the sum of its proper divisors (2845).
406643 is a wasteful number, since it uses less digits than its factorization.
406643 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 2844.
The product of its (nonzero) digits is 1728, while the sum is 23.
The square root of 406643 is about 637.6856592397.
The cubic root of 406643 is about 74.0862762892.
The spelling of 406643 in words is "four hundred six thousand, six hundred forty-three".