643466436 has 12 divisors (see below), whose sum is σ = 1501421712. Its totient is φ = 214488808.

The previous prime is 643466431. The next prime is 643466437. The reversal of 643466436 is 634664346.

It is a tau number, because it is divible by the number of its divisors (12).

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

It is not an unprimeable number, because it can be changed into a prime (643466431) 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, 26811090 + ... + 26811113.

It is an arithmetic number, because the mean of its divisors is an integer number (125118476).

Almost surely, 2^643466436 is an apocalyptic number.

It is an amenable number.

643466436 is an abundant number, since it is smaller than the sum of its proper divisors (857955276).

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

643466436 is a wasteful number, since it uses less digits than its factorization.

643466436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53622210 (or 53622208 counting only the distinct ones).

The product of its digits is 746496, while the sum is 42.

The square root of 643466436 is about 25366.6402189963. The cubic root of 643466436 is about 863.3269524762.

The spelling of 643466436 in words is "six hundred forty-three million, four hundred sixty-six thousand, four hundred thirty-six".