644141164 has 6 divisors (see below), whose sum is σ = 1127247044. Its totient is φ = 322070580.

The previous prime is 644141153. The next prime is 644141209. The reversal of 644141164 is 461141446.

It is a happy number.

It is an unprimeable number.

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, 80517642 + ... + 80517649.

Almost surely, 2^644141164 is an apocalyptic number.

It is an amenable number.

644141164 is a deficient number, since it is larger than the sum of its proper divisors (483105880).

644141164 is a wasteful number, since it uses less digits than its factorization.

644141164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161035295 (or 161035293 counting only the distinct ones).

The product of its digits is 9216, while the sum is 31.

The square root of 644141164 is about 25379.9362489349. The cubic root of 644141164 is about 863.6286037359.

The spelling of 644141164 in words is "six hundred forty-four million, one hundred forty-one thousand, one hundred sixty-four".