639097 has 4 divisors (see below), whose sum is σ = 649636. Its totient is φ = 628560.

The previous prime is 639091. The next prime is 639137. The reversal of 639097 is 790936.

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

It can be written as a sum of positive squares in 2 ways, for example, as 215296 + 423801 = 464^2 + 651^2 .

It is a cyclic number.

It is not a de Polignac number, because 639097 - 2¹⁹ = 114809 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 3 ways as a sum of consecutive naturals, for example, 5178 + ... + 5299.

It is an arithmetic number, because the mean of its divisors is an integer number (162409).

2⁶³⁹⁰⁹⁷ is an apocalyptic number.

It is an amenable number.

639097 is a deficient number, since it is larger than the sum of its proper divisors (10539).

639097 is a wasteful number, since it uses less digits than its factorization.

639097 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10538.

The product of its (nonzero) digits is 10206, while the sum is 34.

The square root of 639097 is about 799.4354257850. The cubic root of 639097 is about 86.1368382218.

The spelling of 639097 in words is "six hundred thirty-nine thousand, ninety-seven".