1643424 has 96 divisors (see below), whose sum is σ = 4898880. Its totient is φ = 479232.

The previous prime is 1643423. The next prime is 1643431. The reversal of 1643424 is 4243461.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 1643394 and 1643403.

It is not an unprimeable number, because it can be changed into a prime (1643423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30982 + ... + 31034.

It is an arithmetic number, because the mean of its divisors is an integer number (51030).

2^1643424 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1643424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2449440).

1643424 is an abundant number, since it is smaller than the sum of its proper divisors (3255456).

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

1643424 is a wasteful number, since it uses less digits than its factorization.

1643424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102 (or 94 counting only the distinct ones).

The product of its digits is 2304, while the sum is 24.

The square root of 1643424 is about 1281.9609978467. The cubic root of 1643424 is about 118.0093835303.

Adding to 1643424 its reverse (4243461), we get a palindrome (5886885).

The spelling of 1643424 in words is "one million, six hundred forty-three thousand, four hundred twenty-four".