644719161473 has 8 divisors (see below), whose sum is σ = 645024959208. Its totient is φ = 644413428864.

The previous prime is 644719161433. The next prime is 644719161529. The reversal of 644719161473 is 374161917446.

It can be written as a sum of positive squares in 4 ways, for example, as 4123823089 + 640595338384 = 64217^2 + 800372^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 644719161473 - 2¹⁴ = 644719145089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (644719161433) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40970915 + ... + 40986647.

It is an arithmetic number, because the mean of its divisors is an integer number (80628119901).

Almost surely, 2^644719161473 is an apocalyptic number.

It is an amenable number.

644719161473 is a deficient number, since it is larger than the sum of its proper divisors (305797735).

644719161473 is a wasteful number, since it uses less digits than its factorization.

644719161473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32563.

The product of its digits is 3048192, while the sum is 53.

The spelling of 644719161473 in words is "six hundred forty-four billion, seven hundred nineteen million, one hundred sixty-one thousand, four hundred seventy-three".