639147 has 16 divisors (see below), whose sum is σ = 910080. Its totient is φ = 398112.

The previous prime is 639143. The next prime is 639151. The reversal of 639147 is 741936.

It is a happy number.

639147 is nontrivially palindromic in base 15.

It is an interprime number because it is at equal distance from previous prime (639143) and next prime (639151).

It is not a de Polignac number, because 639147 - 2² = 639143 is a prime.

It is an Ulam number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 639147.

It is not an unprimeable number, because it can be changed into a prime (639143) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3993 + ... + 4149.

It is an arithmetic number, because the mean of its divisors is an integer number (56880).

2⁶³⁹¹⁴⁷ is an apocalyptic number.

639147 is a deficient number, since it is larger than the sum of its proper divisors (270933).

639147 is a wasteful number, since it uses less digits than its factorization.

639147 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242.

The product of its digits is 4536, while the sum is 30.

The square root of 639147 is about 799.4666972426. The cubic root of 639147 is about 86.1390844795.

The spelling of 639147 in words is "six hundred thirty-nine thousand, one hundred forty-seven".