643379800 has 72 divisors (see below), whose sum is σ = 1740106260. Its totient is φ = 220584000.

The previous prime is 643379747. The next prime is 643379801. The reversal of 643379800 is 8973346.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643379801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 23026 + ... + 42625.

Almost surely, 2^643379800 is an apocalyptic number.

It is an amenable number.

643379800 is an abundant number, since it is smaller than the sum of its proper divisors (1096726460).

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

643379800 is a wasteful number, since it uses less digits than its factorization.

643379800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65681 (or 65665 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 40.

The square root of 643379800 is about 25364.9324856188. The cubic root of 643379800 is about 863.2882047671.

The spelling of 643379800 in words is "six hundred forty-three million, three hundred seventy-nine thousand, eight hundred".