638469047 has 2 divisors, whose sum is σ = 638469048. Its totient is φ = 638469046.

The previous prime is 638469011. The next prime is 638469049. The reversal of 638469047 is 740964836.

638469047 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 638469047 - 2¹⁶ = 638403511 is a prime.

Together with 638469049, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 638468992 and 638469010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (638469049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319234523 + 319234524.

It is an arithmetic number, because the mean of its divisors is an integer number (319234524).

Almost surely, 2^638469047 is an apocalyptic number.

638469047 is a deficient number, since it is larger than the sum of its proper divisors (1).

638469047 is an equidigital number, since it uses as much as digits as its factorization.

638469047 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 870912, while the sum is 47.

The square root of 638469047 is about 25267.9450490142. The cubic root of 638469047 is about 861.0861735642.

The spelling of 638469047 in words is "six hundred thirty-eight million, four hundred sixty-nine thousand, forty-seven".