644026002 has 32 divisors (see below), whose sum is σ = 1330380288. Its totient is φ = 207732096.

The previous prime is 644025989. The next prime is 644026027. The reversal of 644026002 is 200620446.

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 15 ways as a sum of consecutive naturals, for example, 9343 + ... + 37085.

It is an arithmetic number, because the mean of its divisors is an integer number (41574384).

Almost surely, 2^644026002 is an apocalyptic number.

644026002 is an abundant number, since it is smaller than the sum of its proper divisors (686354286).

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

644026002 is a wasteful number, since it uses less digits than its factorization.

644026002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27874.

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 644026002 is about 25377.6673868975. The cubic root of 644026002 is about 863.5771330694.

Adding to 644026002 its reverse (200620446), we get a palindrome (844646448).

The spelling of 644026002 in words is "six hundred forty-four million, twenty-six thousand, two".