644130100 has 36 divisors (see below), whose sum is σ = 1416925804. Its totient is φ = 254119680.

The previous prime is 644130089. The next prime is 644130103. The reversal of 644130100 is 1031446.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 15023376 + 629106724 = 3876^2 + 25082^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644130103) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 36819 + ... + 51418.

Almost surely, 2^644130100 is an apocalyptic number.

It is an amenable number.

644130100 is an abundant number, since it is smaller than the sum of its proper divisors (772795704).

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

644130100 is a wasteful number, since it uses less digits than its factorization.

644130100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88324 (or 88317 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 644130100 is about 25379.7182805483. The cubic root of 644130100 is about 863.6236590425.

Adding to 644130100 its reverse (1031446), we get a palindrome (645161546).

The spelling of 644130100 in words is "six hundred forty-four million, one hundred thirty thousand, one hundred".