643233900 has 144 divisors (see below), whose sum is σ = 1928376576. Its totient is φ = 165415680.

The previous prime is 643233889. The next prime is 643233901. The reversal of 643233900 is 9332346.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (643233901) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1853527 + ... + 1853873.

It is an arithmetic number, because the mean of its divisors is an integer number (13391504).

Almost surely, 2^643233900 is an apocalyptic number.

643233900 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 643233900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (964188288).

643233900 is an abundant number, since it is smaller than the sum of its proper divisors (1285142676).

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

643233900 is a wasteful number, since it uses less digits than its factorization.

643233900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 568 (or 561 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 30.

The square root of 643233900 is about 25362.0563046453. The cubic root of 643233900 is about 863.2229435372. Note that the first 3 decimals are identical.

The spelling of 643233900 in words is "six hundred forty-three million, two hundred thirty-three thousand, nine hundred".