7638321805 has 4 divisors (see below), whose sum is σ = 9165986172. Its totient is φ = 6110657440.

The previous prime is 7638321797. The next prime is 7638321829. The reversal of 7638321805 is 5081238367.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5675211556 + 1963110249 = 75334^2 + 44307^2 .

It is not a de Polignac number, because 7638321805 - 2³ = 7638321797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 763832176 + ... + 763832185.

It is an arithmetic number, because the mean of its divisors is an integer number (2291496543).

Almost surely, 2^7638321805 is an apocalyptic number.

It is an amenable number.

7638321805 is a deficient number, since it is larger than the sum of its proper divisors (1527664367).

7638321805 is a wasteful number, since it uses less digits than its factorization.

7638321805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1527664366.

The product of its (nonzero) digits is 241920, while the sum is 43.

The square root of 7638321805 is about 87397.4931276636. The cubic root of 7638321805 is about 1969.3941814319.

The spelling of 7638321805 in words is "seven billion, six hundred thirty-eight million, three hundred twenty-one thousand, eight hundred five".