644302230 has 128 divisors (see below), whose sum is σ = 1835882496. Its totient is φ = 142656000.

The previous prime is 644302223. The next prime is 644302247. The reversal of 644302230 is 32203446.

It is a happy number.

644302230 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 644302230.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 432547 + ... + 434033.

It is an arithmetic number, because the mean of its divisors is an integer number (14342832).

Almost surely, 2^644302230 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 644302230, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (917941248).

644302230 is an abundant number, since it is smaller than the sum of its proper divisors (1191580266).

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

644302230 is a wasteful number, since it uses less digits than its factorization.

644302230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1622.

The product of its (nonzero) digits is 3456, while the sum is 24.

The square root of 644302230 is about 25383.1091476202. The cubic root of 644302230 is about 863.7005805116.

Adding to 644302230 its reverse (32203446), we get a palindrome (676505676).

The spelling of 644302230 in words is "six hundred forty-four million, three hundred two thousand, two hundred thirty".