1643426 has 8 divisors (see below), whose sum is σ = 2472960. Its totient is φ = 819108.

The previous prime is 1643423. The next prime is 1643431. The reversal of 1643426 is 6243461.

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

It is a junction number, because it is equal to n+sod(n) for n = 1643395 and 1643404.

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 3 ways as a sum of consecutive naturals, for example, 386 + ... + 1853.

It is an arithmetic number, because the mean of its divisors is an integer number (309120).

2^1643426 is an apocalyptic number.

1643426 is a deficient number, since it is larger than the sum of its proper divisors (829534).

1643426 is a wasteful number, since it uses less digits than its factorization.

1643426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2608.

The product of its digits is 3456, while the sum is 26.

The square root of 1643426 is about 1281.9617779014. The cubic root of 1643426 is about 118.0094314017.

Adding to 1643426 its reverse (6243461), we get a palindrome (7886887).

The spelling of 1643426 in words is "one million, six hundred forty-three thousand, four hundred twenty-six".