644623102 has 16 divisors (see below), whose sum is σ = 1051485840. Its totient is φ = 295152768.

The previous prime is 644623099. The next prime is 644623123. The reversal of 644623102 is 201326446.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 254952 + ... + 257467.

It is an arithmetic number, because the mean of its divisors is an integer number (65717865).

Almost surely, 2^644623102 is an apocalyptic number.

644623102 is a deficient number, since it is larger than the sum of its proper divisors (406862738).

644623102 is a wasteful number, since it uses less digits than its factorization.

644623102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512475.

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 644623102 is about 25389.4289419829. The cubic root of 644623102 is about 863.8439352533.

Adding to 644623102 its reverse (201326446), we get a palindrome (845949548).

The spelling of 644623102 in words is "six hundred forty-four million, six hundred twenty-three thousand, one hundred two".