643611832 has 32 divisors (see below), whose sum is σ = 1248163200. Its totient is φ = 310809600.

The previous prime is 643611811. The next prime is 643611851. The reversal of 643611832 is 238116346.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 138832 + ... + 143392.

It is an arithmetic number, because the mean of its divisors is an integer number (39005100).

Almost surely, 2^643611832 is an apocalyptic number.

643611832 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

643611832 is a deficient number, since it is larger than the sum of its proper divisors (604551368).

643611832 is a wasteful number, since it uses less digits than its factorization.

643611832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5167 (or 5163 counting only the distinct ones).

The product of its digits is 20736, while the sum is 34.

The square root of 643611832 is about 25369.5059471011. The cubic root of 643611832 is about 863.3919726158.

The spelling of 643611832 in words is "six hundred forty-three million, six hundred eleven thousand, eight hundred thirty-two".