638475047 has 12 divisors (see below), whose sum is σ = 756732456. Its totient is φ = 536936400.

The previous prime is 638475043. The next prime is 638475059. The reversal of 638475047 is 740574836.

638475047 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 638475047 - 2² = 638475043 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 638474989 and 638475007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638475043) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 120329 + ... + 125522.

It is an arithmetic number, because the mean of its divisors is an integer number (63061038).

Almost surely, 2^638475047 is an apocalyptic number.

638475047 is a deficient number, since it is larger than the sum of its proper divisors (118257409).

638475047 is a wasteful number, since it uses less digits than its factorization.

638475047 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245918 (or 245911 counting only the distinct ones).

The product of its (nonzero) digits is 564480, while the sum is 44.

The square root of 638475047 is about 25268.0637762374. The cubic root of 638475047 is about 861.0888709024.

The spelling of 638475047 in words is "six hundred thirty-eight million, four hundred seventy-five thousand, forty-seven".