638122307 has 4 divisors (see below), whose sum is σ = 638278056. Its totient is φ = 637966560.

The previous prime is 638122283. The next prime is 638122339. The reversal of 638122307 is 703221836.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 638122307 - 2¹⁸ = 637860163 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638122367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71558 + ... + 79979.

It is an arithmetic number, because the mean of its divisors is an integer number (159569514).

Almost surely, 2^638122307 is an apocalyptic number.

638122307 is a deficient number, since it is larger than the sum of its proper divisors (155749).

638122307 is a wasteful number, since it uses less digits than its factorization.

638122307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155748.

The product of its (nonzero) digits is 12096, while the sum is 32.

The square root of 638122307 is about 25261.0828548580. The cubic root of 638122307 is about 860.9302656742.

The spelling of 638122307 in words is "six hundred thirty-eight million, one hundred twenty-two thousand, three hundred seven".