644113222 has 8 divisors (see below), whose sum is σ = 966339000. Its totient is φ = 322000224.

The previous prime is 644113199. The next prime is 644113247. The reversal of 644113222 is 222311446.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent 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 in 3 ways as a sum of consecutive naturals, for example, 12072 + ... + 37867.

It is an arithmetic number, because the mean of its divisors is an integer number (120792375).

Almost surely, 2^644113222 is an apocalyptic number.

644113222 is a deficient number, since it is larger than the sum of its proper divisors (322225778).

644113222 is a wasteful number, since it uses less digits than its factorization.

644113222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56390.

The product of its digits is 2304, while the sum is 25.

The square root of 644113222 is about 25379.3857687691. The cubic root of 644113222 is about 863.6161158627.

Adding to 644113222 its reverse (222311446), we get a palindrome (866424668).

The spelling of 644113222 in words is "six hundred forty-four million, one hundred thirteen thousand, two hundred twenty-two".