1643243412 has 24 divisors (see below), whose sum is σ = 3957920512. Its totient is φ = 530078400.

The previous prime is 1643243363. The next prime is 1643243417. The reversal of 1643243412 is 2143423461.

It is a super-2 number, since 2×1643243412² = 5400497822162803488, which contains 22 as substring.

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

It is a self number, because there is not a number n which added to its sum of digits gives 1643243412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643243417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2208289 + ... + 2209032.

Almost surely, 2^1643243412 is an apocalyptic number.

1643243412 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1643243412 is an abundant number, since it is smaller than the sum of its proper divisors (2314677100).

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

1643243412 is a wasteful number, since it uses less digits than its factorization.

1643243412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4417359 (or 4417357 counting only the distinct ones).

The product of its digits is 13824, while the sum is 30.

The square root of 1643243412 is about 40536.9388582809. The cubic root of 1643243412 is about 1180.0506087650.

Adding to 1643243412 its reverse (2143423461), we get a palindrome (3786666873).

The spelling of 1643243412 in words is "one billion, six hundred forty-three million, two hundred forty-three thousand, four hundred twelve".