643662312 has 16 divisors (see below), whose sum is σ = 1609155840. Its totient is φ = 214554096.

The previous prime is 643662281. The next prime is 643662317. The reversal of 643662312 is 213266346.

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 (643662317) 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, 13409608 + ... + 13409655.

It is an arithmetic number, because the mean of its divisors is an integer number (100572240).

Almost surely, 2^643662312 is an apocalyptic number.

It is an amenable number.

643662312 is an abundant number, since it is smaller than the sum of its proper divisors (965493528).

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

643662312 is a wasteful number, since it uses less digits than its factorization.

643662312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26819272 (or 26819268 counting only the distinct ones).

The product of its digits is 31104, while the sum is 33.

The square root of 643662312 is about 25370.5008228060. The cubic root of 643662312 is about 863.4145446513.

The spelling of 643662312 in words is "six hundred forty-three million, six hundred sixty-two thousand, three hundred twelve".