639547 has 2 divisors, whose sum is σ = 639548. Its totient is φ = 639546.

The previous prime is 639533. The next prime is 639563. The reversal of 639547 is 745936.

639547 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 639547 - 2¹¹ = 637499 is a prime.

It is not a weakly prime, because it can be changed into another prime (639517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319773 + 319774.

It is an arithmetic number, because the mean of its divisors is an integer number (319774).

2⁶³⁹⁵⁴⁷ is an apocalyptic number.

639547 is a deficient number, since it is larger than the sum of its proper divisors (1).

639547 is an equidigital number, since it uses as much as digits as its factorization.

639547 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22680, while the sum is 34.

The square root of 639547 is about 799.7168248824. The cubic root of 639547 is about 86.1570503248.

The spelling of 639547 in words is "six hundred thirty-nine thousand, five hundred forty-seven".