643222148 has 6 divisors (see below), whose sum is σ = 1125638766. Its totient is φ = 321611072.

The previous prime is 643222141. The next prime is 643222169. The reversal of 643222148 is 841222346.

It can be written as a sum of positive squares in only one way, i.e., 638168644 + 5053504 = 25262^2 + 2248^2 .

It is not an unprimeable number, because it can be changed into a prime (643222141) 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 as a sum of consecutive naturals, namely, 80402765 + ... + 80402772.

It is an arithmetic number, because the mean of its divisors is an integer number (187606461).

Almost surely, 2^643222148 is an apocalyptic number.

It is an amenable number.

643222148 is a deficient number, since it is larger than the sum of its proper divisors (482416618).

643222148 is a wasteful number, since it uses less digits than its factorization.

643222148 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160805541 (or 160805539 counting only the distinct ones).

The product of its digits is 18432, while the sum is 32.

The square root of 643222148 is about 25361.8246189031. The cubic root of 643222148 is about 863.2176864253.

The spelling of 643222148 in words is "six hundred forty-three million, two hundred twenty-two thousand, one hundred forty-eight".