644712352 has 96 divisors (see below), whose sum is σ = 1396180800. Its totient is φ = 291852288.

The previous prime is 644712337. The next prime is 644712359. The reversal of 644712352 is 253217446.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is not an unprimeable number, because it can be changed into a prime (644712359) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1700899 + ... + 1701277.

It is an arithmetic number, because the mean of its divisors is an integer number (14543550).

Almost surely, 2^644712352 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 644712352, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (698090400).

644712352 is an abundant number, since it is smaller than the sum of its proper divisors (751468448).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644712352 is a wasteful number, since it uses less digits than its factorization.

644712352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 518 (or 510 counting only the distinct ones).

The product of its digits is 40320, while the sum is 34.

The square root of 644712352 is about 25391.1865024067. The cubic root of 644712352 is about 863.8838006739.

Adding to 644712352 its reverse (253217446), we get a palindrome (897929798).

The spelling of 644712352 in words is "six hundred forty-four million, seven hundred twelve thousand, three hundred fifty-two".