645224100 has 72 divisors (see below), whose sum is σ = 1880400480. Its totient is φ = 170810880.

The previous prime is 645224089. The next prime is 645224141. The reversal of 645224100 is 1422546.

645224100 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 33964 + ... + 49436.

Almost surely, 2^645224100 is an apocalyptic number.

645224100 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645224100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (940200240).

645224100 is an abundant number, since it is smaller than the sum of its proper divisors (1235176380).

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

645224100 is a wasteful number, since it uses less digits than its factorization.

645224100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15629 (or 15622 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 645224100 is about 25401.2617796833. The cubic root of 645224100 is about 864.1123128602.

Adding to 645224100 its reverse (1422546), we get a palindrome (646646646).

The spelling of 645224100 in words is "six hundred forty-five million, two hundred twenty-four thousand, one hundred".