644046103 has 2 divisors, whose sum is σ = 644046104. Its totient is φ = 644046102.

The previous prime is 644046031. The next prime is 644046107. The reversal of 644046103 is 301640446.

It is a happy number.

Together with previous prime (644046031) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 644046103 - 2²⁵ = 610491671 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (644046107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322023051 + 322023052.

It is an arithmetic number, because the mean of its divisors is an integer number (322023052).

Almost surely, 2^644046103 is an apocalyptic number.

644046103 is a deficient number, since it is larger than the sum of its proper divisors (1).

644046103 is an equidigital number, since it uses as much as digits as its factorization.

644046103 is an evil number, because the sum of its binary digits is even.

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

The square root of 644046103 is about 25378.0634209941. The cubic root of 644046103 is about 863.5861174807.

Adding to 644046103 its reverse (301640446), we get a palindrome (945686549).

It can be divided in two parts, 64404 and 6103, that added together give a palindrome (70507).

The spelling of 644046103 in words is "six hundred forty-four million, forty-six thousand, one hundred three".