644611532 has 12 divisors (see below), whose sum is σ = 1141661976. Its totient is φ = 318422400.

The previous prime is 644611519. The next prime is 644611543. The reversal of 644611532 is 235116446.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 970469 + ... + 971132.

It is an arithmetic number, because the mean of its divisors is an integer number (95138498).

Almost surely, 2^644611532 is an apocalyptic number.

It is an amenable number.

644611532 is a deficient number, since it is larger than the sum of its proper divisors (497050444).

644611532 is a wasteful number, since it uses less digits than its factorization.

644611532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1941688 (or 1941686 counting only the distinct ones).

The product of its digits is 17280, while the sum is 32.

The square root of 644611532 is about 25389.2010902273. The cubic root of 644611532 is about 863.8387669960.

Adding to 644611532 its reverse (235116446), we get a palindrome (879727978).

The spelling of 644611532 in words is "six hundred forty-four million, six hundred eleven thousand, five hundred thirty-two".