643338372 has 24 divisors (see below), whose sum is σ = 1502254656. Its totient is φ = 214284448.

The previous prime is 643338337. The next prime is 643338379. The reversal of 643338372 is 273833346.

It is a super-2 number, since 2×643338372² = 827768521775220768, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 643338372.

It is not an unprimeable number, because it can be changed into a prime (643338379) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3048 + ... + 35999.

It is an arithmetic number, because the mean of its divisors is an integer number (62593944).

Almost surely, 2^643338372 is an apocalyptic number.

It is an amenable number.

643338372 is an abundant number, since it is smaller than the sum of its proper divisors (858916284).

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

643338372 is a wasteful number, since it uses less digits than its factorization.

643338372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40427 (or 40425 counting only the distinct ones).

The product of its digits is 217728, while the sum is 39.

The square root of 643338372 is about 25364.1158332003. The cubic root of 643338372 is about 863.2696749804.

The spelling of 643338372 in words is "six hundred forty-three million, three hundred thirty-eight thousand, three hundred seventy-two".