638445265189 has 4 divisors (see below), whose sum is σ = 642673379680. Its totient is φ = 634217150700.

The previous prime is 638445265177. The next prime is 638445265273. The reversal of 638445265189 is 981562544836.

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 638445265189 - 2¹⁵ = 638445232421 is a prime.

It is a super-2 number, since 2×638445265189² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638445215189) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 2114057019 + ... + 2114057320.

It is an arithmetic number, because the mean of its divisors is an integer number (160668344920).

Almost surely, 2^638445265189 is an apocalyptic number.

It is an amenable number.

638445265189 is a deficient number, since it is larger than the sum of its proper divisors (4228114491).

638445265189 is a wasteful number, since it uses less digits than its factorization.

638445265189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4228114490.

The product of its digits is 49766400, while the sum is 61.

The spelling of 638445265189 in words is "six hundred thirty-eight billion, four hundred forty-five million, two hundred sixty-five thousand, one hundred eighty-nine".