638193757007 has 4 divisors (see below), whose sum is σ = 638195359920. Its totient is φ = 638192154096.

The previous prime is 638193756971. The next prime is 638193757013. The reversal of 638193757007 is 700757391836.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 638193757007 - 2⁸ = 638193756751 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638193757037) 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, 304238 + ... + 1170020.

It is an arithmetic number, because the mean of its divisors is an integer number (159548839980).

Almost surely, 2^638193757007 is an apocalyptic number.

638193757007 is a deficient number, since it is larger than the sum of its proper divisors (1602913).

638193757007 is an equidigital number, since it uses as much as digits as its factorization.

638193757007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1602912.

The product of its (nonzero) digits is 6667920, while the sum is 56.

The spelling of 638193757007 in words is "six hundred thirty-eight billion, one hundred ninety-three million, seven hundred fifty-seven thousand, seven".