644466065551045 has 8 divisors (see below), whose sum is σ = 773404955880480. Its totient is φ = 515542400961360.

The previous prime is 644466065550977. The next prime is 644466065551103. The reversal of 644466065551045 is 540155560664446.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 644466065551045 - 2¹³ = 644466065542853 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3806341815 + ... + 3806511124.

It is an arithmetic number, because the mean of its divisors is an integer number (96675619485060).

Almost surely, 2^{644466065551045} is an apocalyptic number.

It is an amenable number.

644466065551045 is a deficient number, since it is larger than the sum of its proper divisors (128938890329435).

644466065551045 is a wasteful number, since it uses less digits than its factorization.

644466065551045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7612869875.

The product of its (nonzero) digits is 207360000, while the sum is 61.

The spelling of 644466065551045 in words is "six hundred forty-four trillion, four hundred sixty-six billion, sixty-five million, five hundred fifty-one thousand, forty-five".