644748624245 has 32 divisors (see below), whose sum is σ = 870527678976. Its totient is φ = 454387264000.

The previous prime is 644748624211. The next prime is 644748624253. The reversal of 644748624245 is 542426847446.

It is not a de Polignac number, because 644748624245 - 2¹⁸ = 644748362101 is a prime.

It is a Duffinian number.

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 31 ways as a sum of consecutive naturals, for example, 973664 + ... + 1495833.

It is an arithmetic number, because the mean of its divisors is an integer number (27203989968).

Almost surely, 2^644748624245 is an apocalyptic number.

It is an amenable number.

644748624245 is a deficient number, since it is larger than the sum of its proper divisors (225779054731).

644748624245 is a wasteful number, since it uses less digits than its factorization.

644748624245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2469661.

The product of its digits is 41287680, while the sum is 56.

The spelling of 644748624245 in words is "six hundred forty-four billion, seven hundred forty-eight million, six hundred twenty-four thousand, two hundred forty-five".