639099 has 6 divisors (see below), whose sum is σ = 923156. Its totient is φ = 426060.

The previous prime is 639091. The next prime is 639137. The reversal of 639099 is 990936.

639099 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 639099 - 2³ = 639091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (639091) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35497 + ... + 35514.

2⁶³⁹⁰⁹⁹ is an apocalyptic number.

639099 is a deficient number, since it is larger than the sum of its proper divisors (284057).

639099 is a wasteful number, since it uses less digits than its factorization.

639099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71017 (or 71014 counting only the distinct ones).

The product of its (nonzero) digits is 13122, while the sum is 36.

The square root of 639099 is about 799.4366766668. The cubic root of 639099 is about 86.1369280744.

The spelling of 639099 in words is "six hundred thirty-nine thousand, ninety-nine".