639087 has 4 divisors (see below), whose sum is σ = 852120. Its totient is φ = 426056.

The previous prime is 639083. The next prime is 639091. The reversal of 639087 is 780936.

It is a happy number.

639087 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (639083) and next prime (639091).

It is a cyclic number.

It is not a de Polignac number, because 639087 - 2² = 639083 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639083) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106512 + ... + 106517.

It is an arithmetic number, because the mean of its divisors is an integer number (213030).

2⁶³⁹⁰⁸⁷ is an apocalyptic number.

639087 is a deficient number, since it is larger than the sum of its proper divisors (213033).

639087 is a wasteful number, since it uses less digits than its factorization.

639087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213032.

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 639087 is about 799.4291713467. The cubic root of 639087 is about 86.1363889562.

It can be divided in two parts, 6 and 39087, that added together give a palindrome (39093).

The spelling of 639087 in words is "six hundred thirty-nine thousand, eighty-seven".