638841144741 has 4 divisors (see below), whose sum is σ = 851788192992. Its totient is φ = 425894096492.

The previous prime is 638841144737. The next prime is 638841144743. The reversal of 638841144741 is 147441148836.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 638841144741 - 2² = 638841144737 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638841144743) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106473524121 + ... + 106473524126.

It is an arithmetic number, because the mean of its divisors is an integer number (212947048248).

Almost surely, 2^638841144741 is an apocalyptic number.

It is an amenable number.

638841144741 is a deficient number, since it is larger than the sum of its proper divisors (212947048251).

638841144741 is a wasteful number, since it uses less digits than its factorization.

638841144741 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212947048250.

The product of its digits is 2064384, while the sum is 51.

The spelling of 638841144741 in words is "six hundred thirty-eight billion, eight hundred forty-one million, one hundred forty-four thousand, seven hundred forty-one".