639498 has 16 divisors (see below), whose sum is σ = 1303776. Its totient is φ = 209040.

The previous prime is 639493. The next prime is 639511. The reversal of 639498 is 894936.

It is a Curzon number.

It is a nialpdrome in base 15.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 639498.

It is not an unprimeable number, because it can be changed into a prime (639491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 688 + ... + 1323.

It is an arithmetic number, because the mean of its divisors is an integer number (81486).

2⁶³⁹⁴⁹⁸ is an apocalyptic number.

639498 is an abundant number, since it is smaller than the sum of its proper divisors (664278).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

639498 is a wasteful number, since it uses less digits than its factorization.

639498 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2069.

The product of its digits is 46656, while the sum is 39.

The square root of 639498 is about 799.6861884514. The cubic root of 639498 is about 86.1548499114.

The spelling of 639498 in words is "six hundred thirty-nine thousand, four hundred ninety-eight".