422640 has 60 divisors (see below), whose sum is σ = 1421784. Its totient is φ = 112512.

The previous prime is 422627. The next prime is 422657. The reversal of 422640 is 46224.

422640 is a `hidden beast` number, since 4 + 22 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 422640.

It is an unprimeable number.

422640 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 427 + ... + 1013.

2⁴²²⁶⁴⁰ is an apocalyptic number.

422640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 422640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (710892).

422640 is an abundant number, since it is smaller than the sum of its proper divisors (999144).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

422640 is a wasteful number, since it uses less digits than its factorization.

422640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 606 (or 597 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 422640 is about 650.1076833879. The cubic root of 422640 is about 75.0453059594.

Adding to 422640 its reverse (46224), we get a palindrome (468864).

The spelling of 422640 in words is "four hundred twenty-two thousand, six hundred forty".