644232169439 has 8 divisors (see below), whose sum is σ = 682145606448. Its totient is φ = 606320668800.

The previous prime is 644232169409. The next prime is 644232169487. The reversal of 644232169439 is 934961232446.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-644232169439 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644232169409) 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, 231089 + ... + 1158389.

It is an arithmetic number, because the mean of its divisors is an integer number (85268200806).

Almost surely, 2^644232169439 is an apocalyptic number.

644232169439 is a deficient number, since it is larger than the sum of its proper divisors (37913437009).

644232169439 is a wasteful number, since it uses less digits than its factorization.

644232169439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 968185.

The product of its digits is 6718464, while the sum is 53.

The spelling of 644232169439 in words is "six hundred forty-four billion, two hundred thirty-two million, one hundred sixty-nine thousand, four hundred thirty-nine".