1644426 has 48 divisors (see below), whose sum is σ = 4213248. Its totient is φ = 453600.

The previous prime is 1644421. The next prime is 1644437. The reversal of 1644426 is 6244461.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 1644426.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1644421) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3696 + ... + 4116.

It is an arithmetic number, because the mean of its divisors is an integer number (87776).

2^1644426 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1644426, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2106624).

1644426 is an abundant number, since it is smaller than the sum of its proper divisors (2568822).

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

1644426 is a wasteful number, since it uses less digits than its factorization.

1644426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 467 (or 464 counting only the distinct ones).

The product of its digits is 4608, while the sum is 27.

The square root of 1644426 is about 1282.3517458170. The cubic root of 1644426 is about 118.0333622031.

Adding to 1644426 its reverse (6244461), we get a palindrome (7888887).

The spelling of 1644426 in words is "one million, six hundred forty-four thousand, four hundred twenty-six".